GB Enthusiast 403 Error for Premium Content (Nvidia Shield / Android TV)

I've been using the GB Enthusiast app for months and like it a lot. Not long ago, I let my GB subscription expire until this most recent sale.

Unfortunately, I haven't been able to watch any of the premium content since resubscribing. Every premium video presents a 403 error. I've cleared cache and data, and uninstalled/reinstalled the app without any success.

Couldn't find anything online and didn't get a response to the Google Play developer email so I thought I'd check here. Any ideas?

After a week of issues, it appears to have resolved itself this afternoon.