Originally Posted by co.com
System-wide Upgrades issued after Jan. 1, 2011 are eligible for all fares except S, T, K, L, G and N in BusinessFirst markets.
Do they above rules apply when trying to use UA SWUs on Region 2 flights operated with CO metal?
I can't get a straight answer on what CO fare codes are or aren't upgrade-able on TATL CO metal flights using UA SWUs
Thanks very much in advance for clarification!