(1) If there is litigation over the terms, conditions, construction, or enforcement of an interlocal service boundary agreement, the agreement shall be presumed valid, and the challenger has the burden of proving its invalidity.
(2) Notwithstanding part I, it is the intent of this part to authorize a municipality to enter into an interlocal service boundary agreement that enhances, restricts, or precludes annexations during the term of the agreement.