At the first place, it shouldn't "revert" to a different save that you didn't restore. Sounds like checkpoint is rejecting the restore for some reason.
I know for a fact that the save isn't an issue, cause it didn't "revert" to a previous save that I didn't restore.
It's hard to imagine the save is the problem, when I am not having issues with it. If other people report that then sure, but that doesn't seem to be the case right now
For now, make sure you're on the latest Checkpoint, and the latest Atmosphere, and make sure your game is 1.2.0. Check the details one more time.
If it doesn't work, try exporting my save's pcdata.bin with PKHeX, then import that pcdata.bin into your save, then load that edited save into your game
My save is not meant to be "playable" in a traditional sense anyway, it's just a way to hold all the mons.; it isn't at after the E4 or something, it is at the very start of the game.
If you like, you could simply upload a save of yours, then I'll load the pcdata.bin in.
Actually, I'll much prefer you send over the latest save of yours.