What is your leaning as to the accuracy of this 'leak' that Clement will be named? Am starting to have a gut instinct that this is a misdirection leak, and the actual nominee will be someone else. But I have no sources, nor a DC or legal background.
Only once in my career did I know FOR SURE what was happening. I was on staff to the Bicentennial Commission on the Constitution, when Chief Justice Warren Burger resigned so President Reagan could nominate Rehnquist. I knew about that one transaction 30 minutes before the official announcement. That's because Burger traded the Chairmanship of the Commission (at a high salary, appointed by the President, including the firing of the former Chairman, Jepson) for letting Reagan name a new Chief Justice.
Other than that one instance, I offer nothing more than educated guesses on this process.
Congressman Billybob