In a planned community, if the right is originally reserved in the declaration, the declarant, in addition to any other development right, may amend the declaration at any time during as many years as are specified in the declaration for adding additional real estate to the planned community without describing the location of the real estate in the original declaration. The amount of real estate added to the planned community under this section may not exceed 10 percent of the real estate described in Alaska Stat. § 34.08.130(a)(3) and the declarant may not in any event increase the number of units in the planned community beyond the number stated in the original declaration under Alaska Stat. § 34.08.130(a)(4).