Got a bit of a shock on my recent entry - turned out my GE had expired 😲 I never received an email about this and had totally forgotten that it was due! I therefore had to join a many-hours long queue at ORD instead! Thankfully eventually managed to get enough reception to download the mobile CBP app and got through a bit quicker via that route.
However I wanted to get GE back immediately so kicked off my renewal whilst still in the queue. I was impressed to find I got my UK Home Office clearance code within 24h and put it straight into my renewal application - that was then approved within 48h! Very impressed overall with how rapidly it was sorted and means I should at least still get TSA Pre on my flight back. Was also interesting to see the approval notice still gets issued by my original interview location for GE.
I was kicking myself for not remembering it would expire although on the upside at least I've got almost 6 years now until it's next due renewal due to the way they expiry works!