I've been having the same problem with all my flights on AS this year so far. Great to get the complimentary upgrades, but haven't had any success getting the MQMs or MQS yet. Five or six emails to DL CS so far, with original ticket receipts and BPs ... no luck. They just keep saying that U class is ineligible for mileage credit.
http://www.flyertalk.com/forum/delta...-upgraded.html