You should have already received notification of this earlier, and an email reminder today. I will post it here for reference:
Start Date: Sunday 10-Feb-2019 02:00 UTC
End Date: Sunday 10-Feb-2019 06:00 UTC
Duration: 4 hours
Event Type: Planned Maintenance
/ Event Description /
This is a reminder for previously announced maintenance. On 2019-02-10, from 02:00 to 06:00 UTC, engineering teams will be performing maintenance on the hosting server.
During this maintenance, all hosting services including web and email will be unavailable.
This maintenance will migrate hosting to a new server to address hardware issues in the existing server.
Efforts will be made to ensure the maintenance lasts less than 4 hours and to prevent email soft bounces which are warnings that email was not yet delivered. Hard bounces, indicating that email was undeliverable, typically would require 24 hours of downtime. Email will not be delivered during this time, but it will be queued by the sending server and delivered after the maintenance is complete.
We apologize for any inconvenience that this may cause and appreciate your patience.