fullness of time
the proper or destined time.
From POTUS To FLOTUS: A Full (White) House Of AcronymsThe faster we move, the more abbreviations and assorted acronyms we use, and when it comes to talking about the folks who reside at 1600 Pennsylvania Avenue—otherwise known as the White House—there are plenty of acronyms to choose from.
Origin of fullness of time
First recorded in 1550–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019