The closest I can give to a reply is that when I attempted to drive to the Whetstone trailhead from Estacada 2 weekends past, I was stopped by snow at about 3200' and 1 1/2 miles from the trailhead.

LOTS of snow has melted in the last 2-3 weeks.  I think your guess of 4500-5000' is probably pretty realistic.  I was at 4000' last weekend and the only snow I saw was a small bit in a heavily shaded south facing area.  It was about 6" deep, but two weeks prior it was probably 24" deep or more.  I'm guessing that snow is probably almost gone by now (if not completely gone).  I would expect you would see some above 4500', but probably not a whole lot.

If you do venture out, please post your findings.

Folks probably already know this but I was up at Elk Lake 2 weekends ago. We had snow on the road in the morning and all gone by the time we got back there in the early evening. FS46 was open and not really any sign of snow anywhere there. Hiked a bit on the trail around the bottom falls and no snow there either.

I have had two reports on Bull Trails.

The first is that the 7020 road to the Whetstone trailhead is washed out, so 7030 is the way to go. Trails sawed out across the top and down towards Opal Creek.

The second is that the road is clear to Bull of the Woods trail head but there is snow on the trail.

D.