We just did this hike yesterday. There are some really neat campsites between lakes 4 and 5, and some others near 5.
We camped near lake 4, inside the old army pass "bowl." Amazing views. We took new army pass up because I read online that OAP was a little sketchy. We left our campsite around 6 and summitted around 11. We were the only ones on the summit and only saw a few others on the trail up to the summit.
On our way back from the summit we passed several groups of hikers heading up and asked them if they knew the conditions on OAP, and one group said it was fine and we should give it a try.
We took OAP back down. It's completely dry aside from around 20 feet of soft well-trodden snow near the top. The snow is flat but it's on decent exposure. Basically you don't want to slip. It could be a little bit sketchy if you don't have any gear depending on your comfort level. After that 20 feet of snow it's just a beautiful hike down. If you're worried about it, you could take NAP up (I wouldn't want to miss the views on NAP anyways) then check out OAP from the top. All of the snow is within the first 50 feet of the trail from the top. Then you can decide if you're comfortable with it.
Have fun!
