I've been trying everything. I have a new iPhone with 5G, so this time I tried data and tab. This morning it was wifi and tab. In both cases, the blue button wasn't there when the atomic clock said it should be, and I ended up pulling down to refresh anyway. It spun a bit and the blue button showed up, but by the time I got to select group (I'm practicing, not actually in parks) it was full, maybe 2 seconds later.
I'm kind of hoping that it's more to do with not having a reservation today. In that case, our tickets would already be automatically selected, so maybe it would speed things up. Hoping I can figure this out before I'm there on the 23rd.