I don't think they will allow 1.15.2 yet. Mainly for the reason that there is no optifine for said Minecraft version yet. The server lags as is because of everything that's in it, and with 1.15 adding even more things, the lag will just get worse. So yeah, optifine will have to come out first.

never mind i went into my system dialog and deleted the latest update and then i let me play

the new server's texture pack make my game lag so much when i join that it crashes immediately, so plz fix it or delete the texture pack

Yeah i guess :)

Hey I was wondering if you could add NPC's that could walk around and to make it look like a school with lots of kids, i think this would be a great idea to see NPC's walking around and looking like students