2015/12/15 - Emergency Maintenance: IMAP servers
In order to address ongoing problems with the IMAP mail servers (which host your mailboxes), it may be necessary to perform emergency maintenance on them during tonight's minor maintenance period.

If this goes ahead, the IMAP servers will be unavailable for several hours starting at 17:30.

During this time you will be able to send email but not receive it. Any mail received during the maintenance will be queued for later delivery once the maintenance is complete.
This maintenance work turned out to be significantly more complicated than expected, but has now been completed successfully.

Unfortunately there was a period of about an hour when new incoming mail may have been rejected. If this happened, a bounce notification would have been generated with an error reading "Mailbox unknown. Either there is no mailbox associated with this name or you do not have authorization to see it."