[2020] Keep getting this error when trying to use my orbs. The problem is, there is no later.

Oh, that message is really unfortunate; it shouldn’t be showing up until after IKO is released. Short version: you’re fine, just wait a couple hours.

Longer version: If you have unspent orbs, you have the whole next set to spend them. THB orbs will be spendable until M21 comes out. There’s a brief window of ~4h before each set release where we need to turn off the pass to manage the switch. During that window you can’t spend them, but you’ll be able to once IKO is released.