[GAMEPLAY] Can't buy reworked Gangplank's Ult upgrades?

So I decided to try out the newly reworked today and for the most part he works great! He's more interactive and a lot more fun than he used to be, so excellent job on that Rito. Unfortunately, I hit that 500 Silver Serpent marker and, excited to try the new upgrades recalled to the shop and... the upgrades remained greyed-out. Unbuyable. Tried building up more SS coins, no change. Died, nada. Is this a genuine bug or am I dumb and missing something? In case it's relevant I was level 11 and had tier 2 ult.