Re: Theresa May comeback ??
It's all down to who you can rally behind you in order to get the power you need as an ambitious MP.
May was the heroine of the Remainers. She played with the words, in order to try to keep the Brexiteers to heel, but worked for a Remain solution. I think she still enjoys a large Remain support in the HOC.
Boris may have been a Remainer, as well, but his plan was to go with what he thought (correctly, as it turned out) was the Majority (Brexiteers).
That also got him through the election which followed.
Perhaps amusingly, they were both given the EU Brino package to muse over.
And here we are, still waiting at the Church!
Don't shout "But we're out" because there is a long way to go before we accept that idea fully!