Thank you for the answer. You are correct. Turbo Tax did not ask me the question because I told it that I had HDHP coverage for all of 2017. The question is only applicable if I have partial year coverage which I did for 2016. So when I did my 2016 return, TurboTax did ask me if I contributed based on last month rule. I checked my 2016 return. The full amount is reported on there. So like you said this is not really applicable 2017 return.
