I believe Turbotax picked up Last month rule weirdly. Since I was covered by self only HDHP on Dec 1st, it added 3550, then for the Sep, Oct, Nov that I was on family HDHP, added 295.93 x 3. So the contribution limit became $4438. But it did not count anything from my wife's contribution.
So contribution from me (7100) + contribution from my wife (1350) - $4438 = 4012(4011).
