I have several different spritesheets representing different biomes/levels for my project. They're all organised in the same way - walls in one place, enemies in another place, all the same size... etc. The only thing that's different is the pixel art. 

I thought I would be able to set up my regions and name all of the sprites ONCE, export to sliced up sprites, and then reload with the next sheet and export using the already-placed regions etc. However, it looks like this isn't possible, because when I hit "Reload" I get a warning about the regions being deleted. 

Am I missing something or is this not supported? Hope my question makes sense and thank you in advance. 

Edit: Workaround

After playing around, I found a workaround. In case this helps anyone else:

After setting up the regions and sprite data for the first sheet, you can simply "Save As" the resulting json file, open it up in a text editor, and tthen change the image that it points to (put the next spritesheet and this edited json in the same folder). Open the edited .json in Atlas, and it will pull the new image but apply the same region data to it.