They must have dropped AZZ023 in 2016 as that was what I used for my old web site prior to my move in 2015. I just carried it forward to the new site as I couldn’t find, at the time, a better zone to use. Looking at the list, I see that AZZ544 or AZZ545 sound to be closer to my location. Unfortunately the link to the map that would allow me to see the zones returns a 404 error.
Putting in a valid zone definitely fixed the problem, though. Thanks.