You can find a full list of scheduled WALs on our handy-dandy Community Events Calendar - you can also keep an eye on the Watch-Along page.
It looks like the next WAL will be tomorrow (08/30) at 7pm PST/10pm EST for Sweet Tooth! 
Find more information here: Harley’s Crew 📺 Watch-Alongs! Sweet Tooth 💥 MONDAYS (8/16–9/6) @ 7pm PST/10pm EST.