Maintenance for the week of January 27:
• PC/Mac: NA and EU megaservers for patch maintenance – January 27, 4:00AM EST (9:00 UTC) - 8:00AM EST (13:00 UTC)
• ESO Website for maintenance – January 27, 1:00PM EST (18:00 UTC) - 4:00PM EST (21:00 UTC)
The servers will probably be down the whole day, and finish like always, around evening (patch days), unless it will be extended (i remember that my time it always ends around 19:00, i am +3 in time zone) but maybe xbox has different times than pc. I would still expect an 8 hours maintenance.