Cisco created a bug about this issue. The backup file is still usable via CLI restoration. Here is the link to the bug CSCwo70665 : Bug Search Tool

I should probably add that I have tried this in my home lab using Cisco ISE 2.7, 3.1, and 3.3 with no change in behavior.

So, I created a ticket with Cisco TAC a couple of weeks ago in reference to this same issue and my case is still open. Hopefully, this will help some of you. Cisco is still looking into this, but here is I have found to be the issue:***ISE repository...