Sure, that is supported, in fact that's the purpose of the sceduler.
So, make a Genreal timeline and set it to run all week with a priority of low.
and in the "special" morning for two hours you can set the "special" timeline to overlap and set with priority of high which will override the first timeline. What I was trying to say is that, only one time will EVER play but you can use the Scheduler to intelligently select which one wins using priority.
Regards,
Sean - MediaSignage.com