Darn, here I sit with two M return TATL fares (upgraded with Skymiles) booked this month for May travel and 18K MQMs to be earned from each. Now I find out it could be 36K MQMs if I'd only waited. The $400 change fee on international tickets makes it very difficult to consider cancelling and rebooking. Hmmn, on second thought, 18K MQM for $400 and a seat in J might well be worth it. Gotta check it out to see if there is still M availabilty with a Z kicker.