Joyent are performing maintenance upgrades to the Manta service from 2014-04-10T03:30Z until 2014-04-10T04:30Z (ie, 8:30 PM until 9:30 PM, US/Pacific time, Wednesday night.)
During this time, Manta will be unavailable for eight 60-second windows.
This should not interrupt publishes, but may result in spurious 404 and 503 errors fetching packages.
We are currently working to minimize the impact as much as possible.
Update: the correct window is 9.30-10.30pm, time zones are hard.