We will be making our new webmail servers live on 1st December. We are still running Roundcube and Squirrelmail but on new servers. They will also be accessed on a new domain (webmail.aa.net.uk).
You can currently try out the new webmail at: https://webmail.aa.net.uk
The new webmail servers have been live for a while now. From today we are redirecting users of the old webmail servers to the new ones. From a users point of view there is very little that has been changed. Both Roundcube and Squirrelmail are available on the new servers. Do let support know if you have any questions.