Good morning Larry,  full disclosure - I don't file Maryland returns.  However, if I did,  I would file the federal and hold the state returns. Why put yourself through filing amended returns unless it's a money making thing.      If I you explain to your clients they'd have to wait for the state refund because of the changes (which were beyond your control and to their benefit)  they should be happy to wait on state.  It would mean larger state refunds or less balance due.