My account status says premium-subscribed, however none of the premium features are working. I assume this is because my annual subscription is set to renew this month...however I'm unable to renew (no button) presumably because it says I'm currently subscribed.

Yep, I was able to renew on the new month and things work fine. So it seems there may be a bug with premium subscriptions: In the last month of a subscription you can have a period of limbo with no features and no renewal options...perhaps if the expiration day has passed but we are still in the same month.