dnd 3.5e – Does a character remain in a martial stance they no longer know?

A Tome of Battle stance can be initiated as a swift action, and “remains in effect indefinitely…until you change to another stance you know as a swift action.” (p. 38)

If a character gained and initiated a stance via the Martial Stance feat (qualified for using the Martial Study feat), then used Player’s Handbook II retraining rules so they no longer had those feats, is there anything preventing them from remaining in that stance for the rest of their adventuring career?

This question mentions the possibility of “remembering” maneuvers gained through Martial Study, but for some reason–maybe the answer is obvious because there’s somewhere in Tome of Battle that clearly states you can’t do this–the post doesn’t say anything about stances.