Section 151.123 - Procedures: Offer; amendment; acceptance; advance planning agreement(a) The procedures and requirements of § 151.29 also apply to approved advance planning proposals. FAA's offer and the sponsor's acceptance constitute an advance planning grant agreement between the sponsor and the United States. The United States does not pay any of the advance planning costs incurred before the advance planning grant agreement is executed.(b) No grant is made unless the sponsor intends to begin airport development within three years after the date of sponsor's written acceptance of a grant offer. The sponsor's intention must be evidenced by an appropriate written statement in the proposal.