Which GPU to upgrade to from RX 570

So I'm planning on upgrading my GPU in the next few days for my birthday, I currently have an RX 570. 1080p gaming right now but I've got the possibility in the back of my mind to upgrade my monitor at some point later for 1440p. I don't really play AAA games if it means anything.

For what's in stock right now, I'm looking at the RX 6600 for about £250 but there's also the RX 6650 XT for £310, I'm just not sure if it is worth the ~£60 extra for the 6650 XT, or if I should wait for stock or potential price cuts for a different GPU.