Will they completely disappear from purchase history as well or stay there but just won't work on iOS 11?
One possibility is they will make them basically invisible in searches and to iOS 11 devices but still available to iOS 10 and below devices via the developers store page.
I've recently discovered (I appreciate I may be WAY behind the population on this) that items removed from the App Store will still show in my purchase history. But there are 2 exceptions; - Items temporarily unavailable. Some items still show but the dev (I guess it's them) has removed the file for download. You'll see the item in your history but not be able to download it. - Items completely removed. I guess this is when devs let their subscription lapse. These will no longer be in your purchase history & naturally not be downloadable. Downloading your apps to your computer for safe keeping really is one of the best ways to ensure they're all safe, of course providing you keep a 32-bit device handy. There's a number of things that could happen with iOS 11. My fave is the one above, pre iOS apps still showing for iOS 10 devices.
