Originally Posted by
goodeats21
No option to apply the certificate. My take is that if there is ANY metal on the trip except UA/UAX, then the certificate cannot be used.
Correct. At least it's not supposed to. And if it does and you try to use one, it won't ticket.
Of course, the site isn't smart enough to bring up the other options it should accept that don't have the UA metal restrictions - like from a travel bank or registry.