Here is a data point on renewing an expired Global Entry.

Summary:

Global Entry Expired in March 2019. Applied for renewal in May 2019. Just got my approval today (1 Nov 2019). About 5 months to get a renewal on an expired GE approved. However was not required to schedule an interview. I'm all approved and ready to go.

Detail:

I had been living/working in Asia 2014 - 2018. Got the GE in 2014 and also got the APEC Business Travel Card (ABTC) sometime afterwards to go through the priority immigration lines. That was a real life saver as some of the SE Asian countries immigration lines can be quite long. I finished my 4-year overseas assignment in June 2018 and really didn't travel much at all afterwards. Boneheaded out and didn't pay attention that my GE expired March 2019. Found out in April when I was going on an overseas flight for work and didn't get my TSA-pre on a domestic connecting flight. Looked at my card, "Doh!" expired. Luckily I had gotten another APEC card 6 months before the GE expire date so I had an ABTC that still had an expiration date in 2022. Although not sure it's still valid if GE is expired, but it worked in Manila, Singapore, Bangkok, and Seoul.

Got back from the overseas trip and applied for GE renewal in late May. I had read that there was a big backlog so wasn't sure how long my renewal of expired GE would take. It was 5 months to get it approved. My bad for not putting the renewal in before the expire date. I thought for sure that I would move from 'pending' to 'conditional approval' and have to schedule and interview, but apparently not. The status on the TTP dashboard is 'Approved' and in the approval letter is says "You can begin using the program immediately." I assume they will be sending me another card. I sort-of hoping to have to go in and get a new picture as I've lost about 40 pounds since I got the picture last time and look a lot better. :-)