On Saturday, January 15, the AdWords system will be unavailable from approximately 10 a.m. to 2 p.m. PST due to our regularly scheduled system maintenance. While you won't be able to log into your account during this time, your campaigns will continue to run as usual.
AdWords system maintenance typically occurs on the second Saturday of each month during the above times. We'll continue to update you here as we always have, but you may want to take note of our intended dates and times to help you plan for any scheduled downtimes further down the road.
Posted by Gordon Zhu, Inside AdWords crew