BTA (and others, I imagine) will CHOOSE THEIR OWN SPACE.... I have a BTA - intro'd in July - moved 3 times initially (within the first week) BACK to front! Then left it and hoped.... Just this weekend, moved the whole rock to front... So far, so good.
I would never - however - try to wrench the foot loose from it's place, if it has adherred at all! that will only cause injury that will likely kill. I rotated the whole rock!
(What a pain)
Good luck.