No, Z21 has been there for a couple of weeks (last release). Z20 was released today and it's brand new. You don't need to have opened Z21 to see it.
I've been burning through energy collecting from clouds, but the Royal Exchange is my blocking point as the crafts for permits take too long. I'd love to see more items that drop cloud stones like the various wisps which were game-changers for the other permits and e/lantern. I would pay for a cloud stone dropper in a heartbeat!
Z21: 6200RP, 2,455,000 coins, 9 windchaser lanterns, 6 windchaser permits (next to coastline)
Z20: 6300RP, 2,555,000 coins, 10 windchaser lanterns, 7 windchaser permits (to the right of Z21)