Originally Posted by brown069

Bunnie- Another caveat... The companion tickets are un-upgradeable. Period. My wife is silver, and we thought we would be able to request our complimentary upgrades for the L, U, T fares (since we're both medallion), but we can't get in the queue-- and we've tried at the airport, SMS, India, and delta.com.

This changed our strategy a bit for using the companion tix. We're now using them only for short-haul trips or for DL Connection flights that have no F class.