The Beta is not an Open Beta. It is a Closed Beta that requires an invite through various programs or the Beta opt-in lottery. The other option is to get access by purchasing the fancy expansion edition.
Regardless, the Beta is down right now and the playtest is not happening.
Test servers go up and down all the time randomly so those are not part of the announced Maint schedule.
Live servers are UP right now. My guess is the OP has their drop down menu on Beta.