Yes...You maintain a DE HOR/SLR (state of legal residence) no matter where you are stationed, and no matter where you buy a home. That can only be changed with a lot of paperwork and a DD form 2058.
SO you indicate you were a resident of DE on 31 Dec. Your mailing address can be your MD home as that doesn't set your SLR. You can still include your mortgage interest, and property taxes paid as potential itemized deductions. That doesn't change either..
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
