Apparently they are waiting to reveal the name until Charles is back from France tomorrow because he has not seen his new grandson yet.
That is kind of nice of them.
Then why didnít they just say that on Monday?
William's own name wasn't announced for a week and it took nearly two weeks for Beatrice's name to be confirmed. There's no "set" time for an announcement here, but 3 days is hardly excessive IMHO.
I agree with Maria that it's nice to give Charles the chance to meet him before they announce anything.