Status (by robm at Mon Jun 29 02:28 UTC)
We’ve been rolling out some internal code changes on the web servers over the weekend. In general the results of these changes shouldn’t be visible to users, but due to a few undetected bugs here and there, there have been some problems for some users.
We believe most of the issues have been resolved in time for the coming work week, and will be testing over the next few hours to make sure that everything is working well.
The beta server (http://www.fastmail.fm/beta/) maybe continue to have issues over the next few days, and may be unavailable for various periods of time. If you experience any problems using the beta server, just use the regular servers (http://www.fastmail.fm) instead.