@idlewords, I renewed for a year, having signed up in 2014. For me, it's an essential service.
I didn't receive any email about this; the most recent message I have is a password reset in 2017.
Aren't the deep discounts for multi-year renewal tantamount to recapitulating the problem with the original one-time sign up fee? i.e., having to run the service with no recurring revenue.