From: Rabbi Moshe Sofer
To: Rabbi Wolf
The Chasam Sofer resolves the question of how malkos can be administered for shifchah charufah by distinguishing two types of chazakah: chezkas minhag (behavioral presumption), which establishes ha'araah with certainty and cannot be overridden by a bari claim, and chazakah d'mei'ikara (status quo presumption), which presumes continuation to gmar bi'ah but can be contradicted. He also limits the P'nei Yehoshua's principle — that accepting a hasra'ah forecloses later excuses — to cases where the warned party already possessed personal knowledge of the exculpatory fact.
Source: Shu"t Chasam Sofer EH II §103