Del. Code tit. 25 § 81-222
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 that real estate in the original declaration; but, the amount of real estate added to the planned community pursuant to this section may not exceed 10 percent of the real estate described in § 81-205(a)(3) of this title 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 pursuant to § 81-205(a)(5) of this title.
25 Del. C. § 81-222