I was there on the 14th and 15th with plans to attempt the Whitehorse Glacier route via snow gulch. Due to bad timing and snow instability, we called it off and just went camping and had some crevasse rescue drills. I have a trip report on cascade climbers you can check out, but briefly:
There is a huge amount of avy debris in the gulch that can be ascended basically from the trailhead. This makes it pretty convenient. But whatever snow was left on the sides of the drainage was melting very rapidly, so ascending past the first cliff band through the slide alder was a big pain in the ass. Up to 50 degree slide alder slopes. We weren't planning on summiting by that time, but wanted to get some personal beta on it for later. Maybe you are planning on climbing the standard route though? I would say the Whitehorse glacier route looks pretty fun past the cliff band crap, but just be wary of the snow. There was a huge avalanche the weekend before I was there, and the danger from big slabs like that is diminished but I did see a smaller wet slab break down to the smooth rock underneath. The snow near and overlaying the rocks around the glacier seemed the most in question with the warming temps. I would say snow and avalanche assessment skills are still important for this mountain right now.