Originally Posted by
rustykettel
Correct, it's possible that the lower GGU fare classes might sell out, or the fares may be expire or refile at a higher (or lower!) price depending on the lead time.
Note that if the lowest available fare class is your status' instant upgrade, U is open, and it's just you or you+1 companion, it makes more sense to save the GGU and just take the instant upgrade. M or higher qualifies for a Class if Service bonus.
For MVPG75K, H is also an eligible fare. Y, S, B & M have a COS bonus while H does not.
James in Kigali.