Exception:If a pitcher reaches a day(s) of rest threshold while facing a batter, the pitcher may continue to pitch until any one of the following conditions occurs: (1) that batter reaches base; (2) that batter is retired; or (3) the third out is made to complete the half-inning or the game. The pitcher will only be required to observe the calendar day(s) of rest for the threshold he/she reached during that at-bat, provided that pitcher is removed or the game is completed before delivering a pitch to another batter.”
Regular Season Pitching Rules - Baseball and Softball
There is definetly a revert back when it comes to days rest, but there does not seem to be any such exception for the catching version of the rule, seems like when they reach 40 and you want them to catch, you need to yank them, mid at-bat or not.