The app permission settings disappeared after I installed the 100th app on my Z10STL100-3/10.2.1.1925. The permissions reappeared after I deleted/uninstalled one app.
After I first encountered this so-called "disappearing permissions" issue on my Z10, I started experimenting with installing and uninstalling apps from both BlackBerry World and Google Play. At first, it seemed that this issue occurred after I had installed more than a fixed number of apps. That is, installing one more app made the permissions disappear; deleting that app made the permissions reappear. However, further experimentation seemed to disprove my theory. That is, after installing just one app, I might have to delete two or more apps to make permissions reappear, Thus, it occurs to me that perhaps the issue occurs after exceeding some fixed threshhold of permissions. That is, the total count of permissions set by all loaded apps.
The term "disappearing permissions" may be a misnomer and be misleading. The permissions themselves appear to be unchanged. Rather, the software (erroneously?) determines that there are no permissions to display.
I think this issue is a software defect. The developers should investigate and correct it.