A hermit crab doesn’t wait for the new shell to feel familiar. It moves because the old one got too tight.

Moving is prompted by the old arrangement becoming impossible rather than by the new one becoming comfortable. Comfort in a new situation only arrives after you are in it, which means waiting for it before you move is waiting for something that cannot happen in that order.

If you are holding out for a new thing to feel right before committing, notice that the sequence is backwards. Use the tightness of the current situation as the signal instead. Familiarity is not a precondition for the move, it is a consequence of it.