I would just use a tax professional this year. The same thing happened to me with H&R Block online a couple of years ago, although I was never informed by the site that they couldn’t process a half year tax return. So it just processed my MD tax return as if I lived there the full year. I filed the paper form for my half year in DC and wound up getting fined for being only a few dollars off of what I actually owed in DC taxes (it was my first time filing a paper form and it was really confusing.) And since my tax return with MD was also wrong I had to do an amended tax return – two years later I’m still fighting with the MD Comptroller to get back half a year’s taxes. It’s been a nightmare.