Done both as overnights and dayhikes. I agree with Akichow that Shasta is harder, but not that much. As she wrote, the glissade hazard is greater on the Trail Crest chute due to larger boulders at the bottom. A guy lost control and died just a few days after I glissaded it one year. In contrast, Avy Gulch has a good length of run out at Helen Lake and below.
There's a good chance the switchbacks will be good by June 12 anyway.
