Good question!
I've pulled them apart because it was getting so big (and I'm not talking image sizes, I'm talking sheer number of individual images (23K as of chapter 7), number of lines of code and script, number of files even), that even if the total file storage size was under 2GB storage for android and 7+GB for pc/mac/linus) you needed 3-6 GB of actual RAM to run it.
That is is a requirement that can be a challenge for lower-part-of-the-spectrum pc's but is was killing Android devices, and they would definitely not be able to run with another chapter added in.
What's more, it was causing internal issues with the ren'py engine, like what I presume were timing issues querying the images manifest that were making the internal cache mechanisms time out, and the cache and program space fighting for memory, and just booting it could take 30 seconds to a minute (which I had to face every time I wanted to test just making a minor code change).
So keeping going in the same package was just no longer sustainable, and I made a clean break.
They will definitely never be joined into a single package.
