Since Prescott has a contract through 2023, the time to draft a possible replacement is in this draft in the 1st round and set the tone.
However, the owner will never bring the hammer into camp because the bloom would be off his rose. And who knows how Prescott would respond? Some of these coddled babies are so ego fragile that they can't stand the heat. Not saying he is one but no one knows until that happens.
That said, the one thing I would do is sit down with him prior to the draft and explain that so far, the 3/4 of the 160M has not paid off and for the team, all options have to be kept open. Where these teams get in trouble is blindsiding and embarrassing their QB.......with the fragile ego.