Originally Posted by Utskicat

Based on the charts from DL internal process, the agent you got was definitely confusing domestic configs: GUC to FC = J, GUC to D1 = Z. I commented on this yesterday. It seems DL's complex reissue process for GUC/RUC relies mostly on agent following the rules/instructions. Automation does not seem to stop them. So if they wrongly think you can use J space (because they don't realize its a D1 flight) then when they force the manual reissue, you won. In this case, the website was correct, your flight didn't have Z so it wasn't available, the other flights were, and the agent was wrong. But you won, so yay!!!

On the reissued ticket, does it show your upgraded flight as class OV or OK?