There is a customer company that operates about 3,000 iPad devices.
Even if the iOS update delay is set to 30 days or 90 days, about 4% of the devices are updated to the latest iOS version.
I remember that this was an old problem and had a problem since around iOS14.
Since most devices are being used outside the company, it was difficult for operators to find out under what conditions this problem occurs.
The case was opened to find the cause of this problem, but Meraki SM appeared to be operating normally and could not find any special problems.
Eventually, we opened this case to Apple to determine the cause of this problem.
We received an answer from Apple without taking too long.
Apple said the problem that the iOS update delay did not work properly is a problem with iOS and will be solved someday.
Apple's answer was received after 15.2.1 was released, so this problem will continue to this day.
There may be people suffering from these problems, so I share the contents.