can terms in a contract supercede a future event

"Entire agreement" when used in a contract drafting context usually refers to limiting the terms of the contract to what's contained within the four corners of the contract document itself (i.e excluding all other oral or written extraneous documents or discussions) Future hotel policy changes should not be of concern if the parties bargained for and agreed (signed) on whatever terms for the duration of the contract. Anyone who breaches those terms when the contract is executory (in full force) is liable to the other for damages stemming from such a breach.