I was notified of 6-mo pending expiry of my Global Entry, (which I originally got 10 years ago). I applied on that weekend, got approval 9 business days later. I have NOT been back in for an interview either time I renewed it & my new GE card arrived about 2 weeks later! I was mildly shocked but hey, nice to get it out of the way so quickly.
(And it's nice having a 10-year old picture on the new card.)