Full details are given in the release change log.
A new activation system means it will take some time to roll this release out to all customers. We will notify you by email when we are ready for you to update.
If you are updating systems or need to install new copies of Archie-M for any reason, please contact firstname.lastname@example.org.
Addendum: on 29/9/2023 a minor update was released as version 2.6.1 which should work better at sites with proxy servers.