Today we've released UTM 9.502. The release will be rolled out in phases. In phase 1 you can download the update package from our FTP server, in phase 2 we will spread it via our Up2Date servers.
IMPORTANT: The re-join workaround is required after upgrading from 9.501 to 9.502. See: https://community.sophos.com/kb/en-us/126819
[Edit 2017-07-17]: Moved workaround into a KBA.
[Edit 2017-07-18]: Release is available as GA
Has anyone already installed this update yet? If so have you noticed anything else breaking from the update?