I haven't had this issue yet, but I have noticed similarly-related issues regarding layers not appearing properly or disappearing. Namely, masks. But in this instance, it's an entire layer that wasn't showing up. And then, the layer appeared when I scrubbed through my composition. But another layer disappeared.
I've got 128 Gigs of RAM at 5600 Hz and a 3090 GPU with a i9 139500 CPU.
Wasn't having these problems before Beta.