You can view the event schedule to see what scheduled events there are after the planned downtime. The first scheduled event is a Standard Daily event at 12 p.m. Pacific, and after that is a Theros Sealed event at 1 p.m. Pacific.
There's been a few questions around the new schedule and changes that were made. We will be evaluating the schedule for future changes, so format decisions might change.
Again, for more information, be sure to read Mike's article over on MTGO.com.