I applied for a Full Time spot at my employer in December of 2016. I got promoted to full time in January, got retroactive pay all the way to December and applied for insurance. I figured that since I had retroactive pay that my insurance would also go back and it would display that I was covered. I filed my W2 already and said I had insurance all year. I got my 1095-C today and it says "Offer of coverage" January through December but when I look down I see Months of Coverage March to December. Do I need to amend my return?