This is a pretty specific case to which I haven't been able to find any information. Apparently T14 4-piece for us is really great, and a lot of high level players (who have the heroic 2/2 versions) stated they won't be breaking their tier bonus unless they get heroic/thunderforged/tier from ToT.
My T14 4-piece are all LFR pieces. If other players are replacing their heroic 2/2 T14 with heroic ToT gear, should I be replacing my LFR pieces with normal 522 ToT? At what point should I break my T14 4-piece bonus?