Whew, yeah updating on android was an interesting process. As of android 11 (and even more so in 13) file browsing software can't read/write files in the android/data folder, which is where the saves are located. Luckily I got around this by turning on USB debugging and plugging the phone into a computer, then using the computer's file browser to move stuff around.
Interestingly (or possibly intentionally) the new version installed as a completely new app for me (the old one was "EA" the new one is "ExcA") which kept my save files in place making this process a little easier.
Found the old saves in Android/Data/android.build and moved them to their new home in Android/Data/extracurricular.activities.
When I launched the new version of the game my saves were there, but unlockables (extras, the alternate title screen, etc.) were not there. It looks like loading my old saves unlocks them, which is easy enough to do The only thing that doesn't seem to have transferred over is what dialogue I have "read" before, so I can't skip though seen dialogue.
Hope this helps anyone else on Android too!