30 CFR § 1206.117
What reporting adjustments must I make for transportation allowances?
July 29, 2020
(a) If your or your affiliate's actual transportation allowance is less than the amount you claimed on form ONRR-2014 for each month during the allowance reporting period, you must pay additional royalties plus interest computed under §1218.54 of this chapter from the date you took the deduction to the date you repay the difference.
(b) If the actual transportation allowance is greater than the amount you claimed on form ONRR-2014 for any month during the allowance form reporting period, you are entitled to a credit plus interest under applicable rules.