Fridays 6 am PT work for me as I am going to be in California for Fall 2020 and possibly Winter 2021 too. I like if the calls are held every other week.
Fridays at 6am PT can work, but then I would prefer 2x month versus weekly 6am meetings.
I'm still figuring out where I'll be in the fall quarter (US or Germany), but the time should work well for me regardless.
I plan to continue to attend collaboration calls. I think trying out a twice-monthly schedule would be a good idea for the fall. I am available at 6am PT on Friday.