NAHMIAS, Justice.

This case involves challenges to the City of Atlanta's attempted annexation of five areas. The trial court correctly held that the annexations were invalid because at the time they would have become effective, the areas in question were already part of the newly incorporated City of South Fulton and thus ineligible for annexation by Atlanta. Accordingly, we affirm.

1. On April 26, 2016, the Governor signed House Bill 514 ("HB 514"), a local act that incorporated the City of South Fulton ("South Fulton"). Section 1.10 of the act says, in part, "The City of South Fulton in Fulton County is incorporated by the enactment of this charter and is constituted and declared a body politic and corporate under the name of `City of South Fulton.'" Section 1.11 defines the boundaries of South Fulton to "include all unincorporated areas of Fulton County... as such exist on July 1, 2016," and explains that "[t]he boundaries of the city are more particularly described in Appendix A, attached to and made a part of this charter." Appendix A says that South Fulton "shall not include any territory that was annexed into another municipality before July 1, 2016," and it describes all of the areas that are to be a part of South Fulton unless otherwise incorporated.

Section 7.14 of HB 514 provides for a special referendum election to be held on November 8, 2016, for "the purpose of submitting this Act to the qualified voters of the proposed City of South Fulton ... for approval or rejection." Qualified voters are defined in Section 7.13 as "the qualified electors of Fulton County residing within the corporate limits of the City of South Fulton as described by Section 1.11." Section 7.14 then says, "If more than half of the votes cast on such question are for approval of the Act, it shall become of full force and effect; otherwise, it shall thereafter be void and of no force and effect." However, Section 7.15 (a) says, "Sections 1.10 and 1.11 and those provisions of this charter necessary for the special election provided for in Section 7.14 of this charter shall become effective immediately upon this Act's approval by the Governor or upon its becoming law without such approval." Other provisions of HB 514 address things necessary for South Fulton to function after the referendum, such as granting the city "all the powers of self-government not otherwise prohibited by this charter or by general law" and establishing the structure and elections for the city's government.

Shortly after the Governor approved HB 514 on April 26, 2016, the City of Atlanta ("Atlanta") received petitions for annexation from five unincorporated areas of Fulton County contiguous to Atlanta. The communities asking to be annexed (collectively, "the Communities") and the dates the annexation petitions were received are as follows: Cascade Falls on April 29; Cascade Business Corridor on May 16; Danforth Road on May 18; Cascade Manor on May 20; and Cottages at Cascade on June 3. All five petitions requested annexation based on the "60/60 method," see OCGA § 36-36-32, which requires a petition to be signed by at least 60% of the registered voters and by owners of at least 60% of the land in the area proposed for annexation.1

Atlanta's municipal clerk validated the annexation petitions and reported the validations to the Atlanta City Council at the beginning of a public hearing that was held on June 15 for all of the proposed annexations except Cottages at Cascade and on June 28 for Cottages at Cascade.2 On June 20, the City Council approved the four proposed annexations heard on June 15, and the Mayor signed the four annexation ordinances on June 21. On June 28, the City Council approved the Cottages at Cascade annexation, and the Mayor signed the annexation ordinance the same day.3 All of the ordinances said that they would become effective in accordance with applicable provisions of Georgia law.4

On July 19, 2016, Emelyn T. Mays and five other individuals (collectively, "Mays"), who represent each of the proposed annexation areas as residents or property owners, filed a petition for declaratory judgment challenging the annexations in Fulton County Superior Court.5 See OCGA § 36-36-39 (explaining that any resident elector or any property owner in the area may bring a petition for declaratory judgment to challenge an annexation). On August 29, the trial court held an evidentiary hearing, and on September 8, the court issued an order granting Mays's request for declaratory judgment and declaring the annexations null and void on the ground that they were untimely under the terms of HB 514 and thus the Communities were part of South Fulton. In reaching this conclusion, the court expressly rejected Atlanta's contention that HB 514 unconstitutionally conflicts with the general laws governing annexation by municipalities by preventing Atlanta's annexation of the Communities as of July 1, 2016.6

On September 9, 2016, Atlanta filed a notice of appeal to this Court.7 On September 13, Mays filed an emergency motion asking the Court to lift the automatic supersedeas of the trial court's order, see OCGA § 5-6-46 (a), and to expedite the appeal on the ground that the staying of the order would confuse voters as to whether they could vote in the November 8 referendum, make it impossible to describe the borders of South Fulton, and affect the outcome of the referendum by disenfranchising voters within the purportedly annexed areas. After receiving a response from Atlanta, we denied the motion to expedite the appeal, but granted the motion to lift the supersedeas, meaning that the annexations were not in force at the time of the referendum and that qualified electors residing in the Communities were allowed to vote in the referendum. In the referendum election on November 8, 2016, the voters approved HB 514, thus giving it full force and effect.

2. Mays argues that we should now dismiss this appeal as moot, rather than deciding its merits, because the creation of South Fulton was approved in the referendum last November. The voters' approval of HB 514 does not render the act immune from challenge, however. The relief Atlanta seeks is not an injunction of the referendum. Compare Bruck v. City of Temple, 240 Ga. 411, 413, 240 S.E.2d 876 (1977) (explaining that because the election approving a local annexation act had been held, the appellants' request for an injunction of the election was moot). Instead, Atlanta is challenging the boundary-setting provisions of HB 514. Relief remains available for this challenge because if it were successful, then South Fulton's boundaries were substantially misidentified and the vote approving HB 514 was invalid, not only because people who did not reside within South Fulton were allowed to vote but also because all of the voters could not have known what particular incorporated area they were voting to approve.8 Thus, Atlanta's contentions — first, that the Communities were properly annexed into Atlanta before they became part of South Fulton under the terms of HB 514 and second, that if they were not, HB 514 is unconstitutional — are "still alive." Bruck, 240 Ga. at 413, 240 S.E.2d 876 (holding that the appellants' challenge to the local annexation act for failing to provide for the extension or creation of wards was not moot after the referendum because it was alleged that "this omission from the local act renders it unconstitutional from its inception"). See also Wall v. Bd. of Elections, 242 Ga. 566, 568-571, 250 S.E.2d 408 (1978) (holding that the appellants' request to enjoin the referendum on an annexation act was moot because the referendum had been held, but addressing the merits of other challenges to the act).9

3. We turn now to the interaction between HB 514 and Atlanta's attempted annexations and specifically the question of whether the annexations were accomplished in time to remove the Communities from the unincorporated areas of Fulton County that became the City of South Fulton. The portions of HB 514 most pertinent to this question are those defining the boundaries of South Fulton — Section 1.11 and Appendix A. As mentioned previously, Section 1.11 defines the boundaries of South Fulton as "all unincorporated areas of Fulton County ... as such exist on July 1, 2016 ... [and as] more particularly described in Appendix A," which says that South Fulton "shall not include any territory that was annexed into another municipality before July 1, 2016." Atlanta argues that Section 1.11 and Appendix A are inconsistent because Section 1.11 sets the annexation deadline on July 1 and Appendix A sets it before July 1. But Section 1.11 specifically refers to Appendix A as describing South Fulton's boundaries "more particularly," and Appendix A says particularly that if territory was not annexed into another city before July 1, it became part of South Fulton.

Atlanta also argues that the Communities should never have been considered a part of South Fulton for two reasons: first, because the areas were made part of Atlanta before July 1; and second, because the part of HB 514 setting the date for defining South Fulton's boundaries should be construed as merely directory and the date moved later to allow for Atlanta's annexations. Atlanta raised these arguments only in its reply brief, after similar arguments were made in an amicus curiae brief filed by a group of residents from the Communities who support Atlanta's annexations. An appellant that raises an argument for the first time in a reply brief is not entitled to have that argument considered. See, e.g., Dallow v. Dallow, 299 Ga. 762, 779, 791 S.E.2d 20 (2016); Higbee Co. v. Solomon, 334 Ga.App. 884, 889, 780 S.E.2d 490 (2015). But even if we consider these arguments, it is clear that they lack merit (which may explain Atlanta's delay in raising them).

(a) Each of Atlanta's five annexation ordinances recited that it would become effective as provided by Georgia law. The general rule in Georgia law is that a municipal ordinance becomes effective when it is signed and filed by the Mayor unless there is a constitutional or general statutory provision governing the matter. See City of Atlanta v. East Point Amusement Co., 222 Ga. 774, 776, 152 S.E.2d 374 (1966). In this case, there is a pertinent statutory provision altering the rule. OCGA § 36-36-2 (a) sets the effective date of annexations done "other than by local Act."10 The statute provides special effective dates for purposes of ad valorem taxes and independent school systems, but it says that "for all other purposes [such annexations] shall become effective on the first day of the month following the month during which the requirements of Article 2, 3, or 4 of this chapter [which provide the three methods for municipal annexations], whichever is applicable, have been met." OCGA § 36-36-2 (a).

Atlanta claims that determining whether the Communities were part of Atlanta before July 1 is not one of those "other purposes." Instead, Atlanta argues that we should look at when the annexations "occurred," and contends that the annexations "occurred" as soon as the Mayor signed each ordinance in June. In support of this argument, Atlanta asserts that OCGA § 36-36-2 (a) indicates that an annexation "occurs" before it becomes "effective" because the statute says that for ad valorem tax purposes, the act "shall become effective ... on December 31 of the year during which such annexation occurred." We need not decide what "occurred" means regarding the effective date of the tax aspects of the annexation ordinances, however, because it is clear that no portion of the ordinances had any legal import before July 1. See OCGA § 36-36-2 (a). See also Columbus, Georgia Consolidated Government v. Schmidt, 269 Ga. 723, 724, 507 S.E.2d 435 (1998) (looking at the effective date of the ordinance to determine when its provisions took effect). Thus, there was no effective annexation until July 1, and HB 514 requires that territory be "annexed" before July 1 to be removed from South Fulton.11

(b) Atlanta alternatively argues that if the annexations were not accomplished before July 1, 2016, the trial court should have treated the July 1 deadline as merely directory and moved it back one day to allow Atlanta's annexations to take effect. Atlanta bases this argument on Section 7.17 of HB 514, which says:

The provision goes on to discuss two specific applications of this rule, stating that if it is not possible to hold the referendum election or first municipal election on the date specified in the act, such election should be held "as soon thereafter as is reasonably practicable."

As indicated by its text and these examples, Section 7.17's proviso for delay applies to dates when the actions called for by HB 514 must be done; many such actions are specified in the act, including the holding of the initial elections and various actions transitioning government functions from Fulton County to the new city. But HB 514 does not mandate that any action occur on July 1; instead, that is simply the day on which the boundaries of South Fulton were settled under the terms of Section 1.11 and Appendix A. And even if July 1 could be construed as the date when the "action" of determining the boundaries had to be completed, Atlanta has offered no reason why it was "necessary to delay [this] action" to further the intent of HB 514. Atlanta's desire to annex the Communities before they could become part of South Fulton is not such a reason. To the extent Atlanta argues that delay was necessary to ensure HB 514's constitutionality, we now turn to — and reject — the argument that HB 514 would be unconstitutional if it did not allow Atlanta's annexations.

4. Atlanta argues that if HB 514 is construed as preventing its annexations of the Communities on (or even after) July 1, 2016, then the act is unconstitutional and thus void. And because HB 514 is void, the argument continues, the Communities are not part of South Fulton and were subject to annexation by Atlanta on July 1. Atlanta's argument hinges on the Uniformity Clause of the Georgia Constitution, which says in relevant part that "no local or special law shall be enacted in any case for which provision has been made by an existing general law." Ga. Const. of 1983, Art. III, Sec. VI, Par. IV (a). The parties agree that HB 514, which applies only to the unincorporated areas of Fulton County, is a local law. They disagree about whether any general law precludes the act.

Atlanta contends that HB 514 conflicts with the general laws that give cities the power to annex contiguous, unincorporated areas when the city meets the requirements of one of three annexation methods set forth in what we will call the "Municipal Annexation Statutes."12 In particular, Atlanta claims that HB 514 violates the Uniformity Clause by preventing Atlanta from annexing the Communities pursuant to OCGA § 36-36-32 (a) beginning on July 1, 2016. We find no intersection, however, between the general Municipal Annexation Statutes, which delegate to municipalities limited power to annex territories, and HB 514, a local law exercising the General Assembly's exclusive power to incorporate municipalities.

(a) To begin with, the general law on which Atlanta relies for its purported authority to annex the Communities does not permit a city to annex territory that is already part of another city; OCGA § 36-36-32 (a), which is quoted in full in footnote 1 above, authorizes municipalities to annex only contiguous "unincorporated areas." And, as discussed in Division 3 above, under HB 514 the Communities were already part of the City of South Fulton when Atlanta's annexations would have become effective on July 1, 2016.

We note that on this point, the trial court's analysis was slightly off-base. While the court concluded that HB 514 put a "hold" on the Communities on July 1, pending the November 8 referendum, HB 514 actually incorporated these areas. Section 7.15 of the act says clearly that Sections 1.10 and 1.11, which incorporate South Fulton and define its boundaries, became effective when the Governor approved the act, which he did on April 26, 2016, and Sections 1.11 and Appendix A fixed the city's boundaries as of July 1. See also OCGA § 1-3-4 (b) ("[L]ocal legislation and resolutions intended to have the effect of law become effective immediately upon approval by the Governor or upon their becoming law without his approval, unless a different effective date is specified in the Act or resolution."). Compare City of Brookhaven v. City of Chamblee, 329 Ga.App. 346, 350, 765 S.E.2d 33 (2014) (holding that the annexation aspect of the local law was not effective upon the Governor's signature because the act provided that "it would only become effective on December 30, after a positive referendum vote").13

Once the Communities were incorporated along with the rest of South Fulton, OCGA § 36-36-32 (a), a general law, prevented Atlanta from annexing them.14 Indeed, if we were to conclude that HB 514 unconstitutionally impinged on Atlanta's annexation power, the General Assembly could never incorporate land contiguous to an existing city, because any such action (which is done by local law) limits the existing city's potential annexation power by withdrawing some land from its reach.

(b) More importantly, the trial court was correct in concluding that the annexation power of cities is subordinate to the General Assembly's power to annex and incorporate. Atlanta argues that the General Assembly's power to incorporate South Fulton by local law was precluded because the Municipal Annexation Statutes regulate how the boundaries of cities may be changed and thus occupy that regulatory field. This Court has explained that the Uniformity Clause "was intended to insure that once the legislature entered a field by enacting a general law, that field must thereafter be reserved exclusively to general legislation and could not be open to special or local laws." Hudgins, 193 Ga. at 623, 19 S.E.2d 508. See also Franklin County v. Fieldale Farms Corp., 270 Ga. 272, 274-275, 507 S.E.2d 460 (1998).

However, the field that the Municipal Annexation Statutes occupy is not how all city boundaries are established, but rather only how the boundaries of existing cities may be changed by those cities under the limited annexation powers delegated to them by the General Assembly. Indeed, OCGA § 36-36-10 ensures that the Municipal Annexation Statutes cannot be misinterpreted to limit the General Assembly's primary power over annexation, saying:

The only express limitation the legislature has placed on its own authority to annex by local act is OCGA § 36-36-16, which does not apply to this case.15

Furthermore, this Court has squarely held that the Municipal Annexation Statutes do not limit the General Assembly's power to control the boundaries of cities. In City of Fort Oglethorpe v. Boger, 267 Ga. 485, 480 S.E.2d 186 (1997), the Court held that the General Assembly's annexation of a non-contiguous area into the City of Fort Oglethorpe by local act was valid even though municipalities are limited to annexing contiguous areas and some language in OCGA § 36-36-50 could be read as limiting all annexations to contiguous areas. See id. at 485-486, 480 S.E.2d 186. See also Lee v. City of Jesup, 222 Ga. 530, 531, 150 S.E.2d 836 (1966) ("The existence of prior statutes permitting the enlargement of boundaries does not deprive the General Assembly of the power to alter and extend municipal boundaries without the consent of the persons affected thereby.").

The Court of Appeals applied a similar rationale in City of Brookhaven, which presented circumstances analogous to those here. In that case, the General Assembly passed a local act that "established boundaries for an area of land (the `Annexation Area') for annexation by the City of Chamblee." City of Brookhaven, 329 Ga.App. at 346, 765 S.E.2d 33. The act also provided for a referendum election on the annexation. See id. After the act was signed but before the referendum could take place, Brookhaven attempted to annex part of the Annexation Area. See id. at 349, 765 S.E.2d 33. Citing OCGA § 36-36-10, the Court of Appeals correctly concluded that Brookhaven could not annex land out of the Annexation Area, concluding that "the General Assembly did not intend the alternative methods of annexation to establish a system for municipalities to race the legislature to annex land that it already has designated for annexation under local law." Id. at 352, 765 S.E.2d 33.

Perhaps recognizing that OCGA § 36-36-10 and the related annexation precedents are fatal to its case, Atlanta asserts that the issue here is not annexation but incorporation. In the field of incorporation, however, Atlanta's argument finds even less support. The General Assembly has exclusive power to incorporate municipalities, see Lee, 222 Ga. at 531-532, 150 S.E.2d 836, and general laws delegating some annexation power to existing municipalities certainly do not occupy the field of incorporation. The General Assembly has enacted some general laws to "prescribe certain minimum standards which must exist as a condition precedent to the original incorporation of a municipal corporation of this state," OCGA § 36-31-1, but Atlanta does not contend that HB 514 violates any of those standards. See OCGA § 36-31-2 to 36-31-12.16

For these reasons, we reject Atlanta's argument that HB 514 violates the Uniformity Clause.

3. Because the City of Atlanta did not annex the five Communities before they became part of the City of South Fulton by the terms of HB 514, a constitutionally valid local act, the trial court's ruling that Atlanta's annexations were invalid was correct. We therefore do not need to address the other arguments raised by Mays and relied on by the trial court as alternative reasons for holding that Atlanta's annexations were invalid.

Judgment affirmed.

All the Justices concur.