As was mentioned somewhere, no faction leader will plan a city take over during peak hours. They need to take keeps and BOs then queue up for the appropriate zones scenerio and hope the other faction does not sign up for it as well. All you have to do is queue up, if the scenerio doesn't pop, you are awarded victory points for the area. And if everybody is in bed...thats easy money or victory points.
The only thing I can think we can do as a guild, is to get as many T4s on to take back what destro has been taking. If we want to fight it head on, 2am is too stupid a time for me and probably for a lot. But those who are up at 2am taking stuff are busy napping during peak time. So we would need to be really smart about it. And worst case scenerio, hope there are enough people on during a fortress assault to defend it, or enough people on during a city assault to force a reset on destro's failure.
EDIT:
When I was on last night, I checked in on the two T4 zones that are contested, they didn't appear in any more or less danager then normal.