What I recall is them doing the same thing they have done throughout history--barely say, "Oops," blame it on the flock for misinterpreting, and start on the next prediction. Just research the false predictions they had in the 1800s forward and a pattern emerges.
I just remembered some dumbasses in 1976 saying it was the King of the South's* bicentennial year that was being celebrated--wouldn't it be fitting if jehoopla struck down their pride with Armageddon?
So basically they just moved on to the next date to look forward when billions would be executed and their bodies would be eaten by birds.
*sorry if I've got that wrong--I don't remember my kings, just that giant statue with the crossed arms and crumbling feet lol