Wow, playing from home I had some wonkiness happening for the first time in about 2 weeks. For reference, Galaxy S8, WIFI, Android Pie OS.
At exactly 9:00, app was already open and hit "Find Out More." Surprisingly, grey button. Quick back out, back in and button still grey...hmmm...
Quick app reboot, again, still grey but now...My Status > Join Boarding Group is active...I will say it seems Iphone users have better luck on this screen based on the blogs/YoutTube videos I've seen. They seem to click My Status at 8:59 and continually refresh. However, doing that, FOR ME, seems to hang the app and the blue circle of death spins with no last updated time.
Results of all this? I still think app already open and hitting Find out More at precisely 9:00 local time or park open is the best for me on Android Pie, Galaxy phone. IPhone seems to be the other way via my status however we will get to try all of this next month...live and in person!