Probably plenty of threads on this so perhaps someone could point me in the right direction?

Just flew IAD-LHR yesterday and sat in CW which I'd managed to snag a rare avios upgrade a few weeks before. Because it's been upgraded, to me there's not a huge difference if you sit in an older, non upgraded 777 which a quick look at the IFE and the masses behind me cramped into their seats confirmed it was a non upgraded one.

Having said that a few weeks prior I flew LHR-IAD and got a last minute upgrade to WTP which was a relief because I think the new WTP product is really excellent. Such was my disappointment at boarding to see it was the old WTP which I find far less comfortable, no power outlets and the old IFE.

So Sunday I'm flying back to IAD and with the chance of a CW upgrade not on the cards, I'm just wondering a few things..

-Is there any way of telling what plane I'll be on? (what type, as I know it's a 777)
-Is there anyway to tell if WTP has been upgraded?
-How many 777s have the upgraded WTP/WT cabins?
-Is there any particular roots they fly the upgraded or non upgraded ones on? I flew this exact route a few months before and was on an upgraded one but previous 2 have not had the upgraded seats