Android C++ - Migrate save files from card to external dir?

To upgrade to 4.16 and avoid annoying/scary realtime permissions, I want to check “Use External Files Dir”

I have a game that has been on the store for a while though, so thousands of people already have save data on the card. This means they would see progress wiped out if the save folder moved. So my thought was to dig into the engine code and figure out how to migrate the files over for existing players.

However, after looking at the engine code, it seems that the save folder url cannot be changed at runtime, it is generated of the packaging. Also I get a bit over my pay-grade at that low of a level.

Looking for a suggestion on how to toggle between the two folder locations at runtime so I can migrate the save data from the old folder to the new. (or any solution really…)

Please see this thread for more discussion of the issue:
https://forums.unrealengine.com/development-discussion/android-development/124642-save-game-system-changed-between-4-14-and-a-follow-up

Answer is found in the forum thread posted in the OP. (Thanks Chris)

In a nutshell: You can use GOBBFilePathBase to get to the old folder.