Castle Level 4 in Suikoden 1 (after Neclord)

I'm trying to finish Suikoden 1 now, so I can finally start 2. I just finished the Neclord part, and have now started the Dragon's quest. It's not leveling up to Level 4 when I had exactly 90 (including Viktor who just left, and Gremio who 'you know what'). Now I have 92 (recruited Kreutz and Fuma over at the Dragon Knight's Fortress). I've counted the Stone Tablet manually, and everyone's there.

Does the castle not level up to Level 4 after Neclord even if you have more than 90 characters?