I've configured NFL games to be recorded and added to my YTTV library.
I go to my library list and during a game that is actually currently being recorded, I select it and I get 3 options: 1) Join Live , 2) Catch up to live through key plays , and , 3) Start from the beginning.
While a game is actually being recorded, options 2 and 3 have stopped working. 2 usually states there aren't any plays available and 3 will simply go to the live game and not have any recorded history to go back.
This is a new behavior and appears to be specific to the Roku YTTV app since I've tried this on both my Android and LG YTTV apps and this functionality works fine.