After creating my previous post, I noticed a relevant new thread on the Help board. In Sheets not updating automatically and not receiving daily email transactions @heather explains the “need to launch the add-on at least once every 14 days” in order to keep Auto Fill enabled. I assumed this would not be an issue for me, since I had just enabled Auto Fill a few days ago. However, after reading Heather’s post, I checked my settings and Auto Fill was disabled.
@heather, thank you for engaging here on the thread to help users figure this out. Can you help me understand what may have caused Auto Fill to be disabled, when I enabled it only a few days ago? Thanks.