It's not just OS update - I use one app in particular that forces regular lengthy update in Windows but never on iOs. There's definitely a pattern here...
You have youre update settings on the ipad set to night time?
As there have been updates.
But then again someone will surely post that exploits vs fixes graph that shows ios and Windows have about the same number of exploits but apple just fixes about a 1/3rd what Windows does so you'll see leas