This version adds support for 1.17 and the ability to change the default world of the game (You can make islands spawn in end for the first time, and have the players unlock the normal world, for example). Alongside of that, plugin modules are now a thing, which means now you can completely turn-off sub-systems of the plugin.
You can see a full change-logs list on the github page.

Please note: I only update stable versions to Spigot. You can find dev builds on our website.
These builds are stable, just weren't fully tested.