Hi Richard, thanks for the detailed explanation. When you updated the APs, did you update with a delta configuration update or a complete configuration update? Delta updates are for smaller changes, so if you ran a delta update you'll want to run a complete configuration update instead (this will reboot the AP, just so you are aware).
If you have already tried a complete configuration update, could you SSH in to the AP,
enable capwap debugs, then try to push a complete configuration update again, wait for that to finish one way or the other, then
pull tech data? Those capwap debugs will give us more information on the update process so we can see if there are any failures in that process within the tech data logs. If you'd like to send the tech data to me for review, my email is community@extremenetworks.com.