Recently conquered Rakata Prime and rebuilt the Star Forge. I dropped a Modular Taskforce Cruiser there to further reduce prices and increase speed as it's my new major shipyard. Worked like a dream, could basically produce a Sith Interdictors as fast as I could click. Loaded it back up today, and all the frigates and corvettes had disappeared from the build menu. Tried scrapping and rebuilding the yards to no effect. Scrapped the MTC and the ships showed back up on the menu.