If you assume an appellant's responsibility to post a bond or other surety instrument or demonstrate financial solvency under § 1243.5, you:

(a) Must notify ONRR in writing at the address specified in § 1243.200(a) that you are assuming the appellant's responsibility under this part;

(b) May not assert that you are not otherwise liable for royalties or other payments under 30 U.S.C. 1712(a), or any other theory, as a defense if ONRR calls your bond or requires you to pay based on your demonstration of financial solvency; and

(c) May end your voluntarily-assumed responsibility for posting a bond or other surety instrument only after the appellant under this part either:

(1) Pays or posts a bond or other surety instrument; or

(2) Demonstrates financial solvency.