If there was a tie-breaker game prior to the playoffs, the rest is messed up for players on the farm team for that tie-breaker.

I don't know if this happens ONLY for teams in the actual tie-breaker or for all teams in the league. I know it happens for teams that play the tie-breaker.

if you have two players with the same usage & BFA level but leave one active and one on the farm team but don't play either one in the game, the guy on the farm team will NOT receive a day of rest but the guy on the active roster WILL get a day of rest.

That might account for some incaccuracies in rest days.