In Bankruptcy Court what is it called when...?

a mortgage lender's "proof of claim" is rejected and the debtor decides to liquidate the property and pay off all the creditors with the value of the property. I think the term is APS or APO? Does anyone know what this abbreviation may stand for? The lender would not want this procedure or motion to happen because they don't have legal standing to foreclose. May only be for Chapter 11, but not sure. Thanks