We don't usually let decision theories make precommitments. That's why CDT fails Newcomb's problem. I think CDT and EDT both converge to something like TDT/UDT when allowed to precommit as far in advance as desirable.

If you want to change what you want, then you've decided that your first-orded preferences were bad. EDT recognizing that it can replace itself with a better decision theory is not the same as it getting the answer right; the thing that makes the decision is not EDT anymore.