Will you also hit the MQD threshold? That’s what always saves me from this situation as I’ve ended a couple of years with more than 125MQMs but was short of $15k MQDS...

I know you can remove your SM number from a reservation, but be sure you’ve selected seats (C+), before doing so because they won’t recognize your status once the number is removed. I don’t think you’ll lose your previously selected seats.

Similarly, you’ll be charged for baggage on domestic flights without your SM number attached (though a check-in agent can waive for you if you ask nicely).