I hear this is a firmware bug, and should automatically sort itself out once we hit March (but there is a bugfixed f/w due too). My pet theory/guess was that there was a misimplementation of some algorithm like Zeller's congruence (https://en.m.wikipedia.org/wiki/Zeller%27s_congruence) for calculating the day of the week, which works on an adjusted year starting in March, because I couldn't come up with any other reason why a leap year bug would manifest for all days before feb 29 and then not thereafter. But there is probably a duller explanation :-)
