I think there's a difference between a T who changes the rules because they are not working versus one who changes the rules just for fun, for the T's own benefit, or just to screw with you.

I believe you have stated, RB, that your T explained her reasoning in the change and you even agreed with it, and/or thought that the changes were for the best.

I think it's unreasonable to think that your T would continue to remain unchanged in the face of evidence that some rule was doing you harm. Or that your T would be like concrete, never moving, no matter what. That would certainly give you permission to go off the deep end and then complain that she can't do anything about it, because the rules should always stay the same.

Ultimately, you can walk away from the rules and rule changes by switching T's, or leaving therapy all together. But I just don't think that complaining that your T changed something is much of a real complaint, when she said she changed it for your benefit and I believe you have reaped the reward of that benefit.