1) Ideally, what you are wanting to do is really beyond the capabilities of a URC CCP system. This is more the territory of URC Total Control - so you also would be looking at 2x the cost of equipment to do everything. Plus you have to be a dealer to even program anything in TC - no consumer is going to be able to get TC software, it's hard enough for dealers to stay approved.

2) With the above said, depending on your equipment brands you want to control, it maybe possible to do this with CCP in a very unconventional way. It is going to involve running a lot of IR signals over Cat5/6 between rooms, not the RF. Breakout boxes with diode isolation. And a bit of trial & error.

3) The easiest way to deal with this however, is not worry about turning other rooms off & on when you are not even in them.
BUT.... since you said you have an HDMI matrix involved.... could the reason you want that kind of control be because the Matrix won't work correctly unless all the TVs are on together? I have seen that with some of the cheap crappy HDMI matrix before.