To expedite the processing of your application for a grant or TUP, BLM may estimate rent payments and require you to pay that amount when it issues the grant or TUP. The rent amount may change once BLM determines the actual rent of the grant or TUP. BLM will credit you any rental overpayment, and you are liable for any underpayment. This section does not apply to rent payments made under the rent schedule in this part.