Are SDC MQM change ever reconciled?

I did a SDC on a ATL-SEA flight, and I was put into "P" class which gave me an extra 1091 MQM miles.
Based on my planned end of year flying, these extra MQM will just put me over to PM status for next year.
Does anyone know if Delta does any type of reconciliation and take away these extra MQMs?
Should I play it safe and make sure to hit a spending threshold or buy some MQM?