[xadhominemx]

Ok, but now your “time boxed” half day refactor is two man weeks of testing, bug fixes, back and forth, etc

[D-Coder]

If you planned your refactor AND testing and bugfixes to take half a day, and it is going to go way over, you (a) tell your boss your estimate was off and the refactoring needs to be a separate task, and (b) revert it.