I can't see anything on the status page, but I've been having some email issues since late last week:
1) If I try to delete or reply to emails via webmail, I get a 403 Forbidden error. Connecting via IMAP using Thunderbird allows me to delete and respond fine
2) webmail.plus.net seems to be unavailable from time-to-time e.g. it was unreachable this morning for about half an hour or so.
3) I'll be moving through emails in webmail and the list will disappear, which usually happens when there's a loss of connection to the IMAP server (although there's no error showing on the web client). Likewise, I might click on an email to read it, and the list disappears, so I have to click on inbox again to reload everything or log out and back in again.
As my broadband connection is currently having problems, I've also been using an EE 4G wi-fi hotspot as backup and same issues are occurring.