Destiny 2 early access was from July 18-20. But today the free open beta on PlayStation 4 and Xbox One begins, running from 10 a.m. PST July 21 through 9 p.m. PST July 23. Without sleep, that's almost 60 hours of playtime. PC early access and open beta to follow in August.
I was going to skip it if the open beta was versus mode only. But it's a pie slice of everything:
Destiny 2 launches on PS4 and Xbox One on September 6, PC on October 24.