Hi, thanks for the report. I’ve fixed this so that the route should validate correctly now.
Note that after you generate your flight plan, the airway in your route might still be renamed to remove the last letter in some cases (i.e. UB404G becomes UB404 after you generate the OFP). But all the waypoints along the airway will still be present and you shouldn’t see any “airway not found” errors.
For now I’m going to keep it this way since it looks like many add-ons don’t support these longer airway names, so dropping the last letter results in better compatibility when importing into said add-ons.