(a) The addition of territory approved under § 452.602 or 452.603 does not take effect if, before the effective date of the addition under Subsection (b), the executive committee of the authority gives written notice to the governing body of the municipality or the commissioners court of the county that held the election that the addition would create a financial hardship on the authority because:
(1) the territory to be added is not contiguous to the territory of the existing authority; or
(2) the addition of the territory would impair the imposition of the sales and use tax authorized by this chapter.
(b) In the absence of a notice under Subsection (a), the addition of territory approved under § 452.602 or 452.603 takes effect on the 31st day after the date of the election.