Does it dump $366 onto Sch A Medical?

Unfortunately the iterative calculation sometimes results in an unsolvable math problem.  When the software encounters this is seems to cough up the difference on Sch A.  If you're in a disaster area you might be able to play around with an IRA or SEP-IRA deduction to see how the numbers change (check the disaster rules to see if the retirement contribution deadline was also extended).  Otherwise it's too late to do much about it.  I've seen situations where a $1,000 IRA contribution lowers AGI enough to save $3,000 in APTC payback.