My sleep schedule tended to drift further into the night as well. I installed f.lux s little over a week ago, and just realized a day ago that I find myself going to bed around midnight consistently! The amount of sleep has also decreased, to about 7.5 hours. sleep quality seems similar. (I'm using ElectricSleep for tracking movement)

Capitalizing on this, I've ordered orange-tinted blue-blocking glasses, and have attempted to find something like f.lux for Android. There are custom ROMs that can do it, and there's apps like Lux that only change brightness. Supposedly you can use Chainfire3D + Chainfire3D Pro + CF.Lumen, although I think that modifies your ROM.

I'm using EasyEyez right now, which can put an ugly red overlay over the screen. I don't know how effective it is, but at least you'll need to reduce blue to go from a white colour to a red colour.

YMMV, my girlfriend didn't notice any change since using f.lux.