Great work YOWgary!

I am running into a situation and two AC agents on phone refused to budge. I have a OW reward flight DEL-FRA-SFO in J with both segments on LH. Now, for FRA-SFO F space opened up (lowest) and it shows on AC search engine. But when I called AC to upgrade that segment to F, they say they can't do it without breaking the ticket. That does not sound right to me.

Any thoughts?