Hi.. I will tell you that in the stations I've worked at before we would, as a rule NOT upgrade the OAL Non-Rev holing Y class into C or (worse yet) into F.. We would however find a UAL non-accompanied spouse (normally only permitted into C) or a unaccompanied companion (again, only entitled to C) and move them into F, to make space.. Unless we were risking a delay (we were never permitted to knowlingly take a delay for non-revs) we'd always do some "controller" upgrades at the gate to ensure everyone got on... This was assuming the meal count and such forth permitted it.. sometimes we only catered F to the revenue ticketed level..