CPFF completion contract and LOE

On a CPFF completion type of a contact is there any concern about holding positions to LOE? Do I as the contractor need to keep track of LOE and do I (contractor) need to state that number to USAID (assuming it is not specifically stated in the contract). If I receive approval from USAID and have stated LOE

- Are we the contracrot - held to that amount of LOE in the approval given by USAID (even though it isn't a CPFF Term contract)

- If we the contractor exceed the LOE, do we need to seek USAID approval and if so, do we get an allowable overage percentage ?