Question about roll back to Lumia Black

[ajcletus500]

If i roll back to lumia black to get the cyan update, will the apps and app data on my sd card be usable after updating to cyan or will i have to delete them all and install them fresh again?? I have some app data that i dont want to lose

 

[WanderingTraveler]

Alright, here's what to try to do.

First, you back up your app data and whatnot.
Then, you flash Black.
After that, update to WP8.1 DP (if you theoretically can, of course.)
Then, hard reset.
Restore data from there.

I don't know if this method works, but it's worth a shot.
Backup is in settings>backup.