I finally got my application for renewal approved, 319 days after applying on Feb. 20, 2020. (Expiration date was in June 2020.)

This was my first renewal of GE. No requirement for an interview. Since I applied for my renewal I had updated both my passport (twice!*) and my driver's license so I was expecting I might have to schedule an interview to update the document information. Nothing "unusual" in my travel history in the last few years, btw. Hope this helps others waiting for their renewals. It does seem that either you get your renewal within a couple of days if you file it now, or you're waiting around 310 days if you filed it early last year.

(*) I renewed my passport in November and the new one they issued wasn't the 52-page version that I had asked for, so I complained and they issued me another one in the 52-page format (free of charge) last month. I guess technically I had one valid passport for just a couple of weeks. Of course, I have no way to tell whether the passport renewals did anything to the GE renewal process in any way.