Android Rollback from 17 to 16

I am very sorry to be posting this but my ability to search doesn’t seem to be returning anything fruitful.

I run Kodi on a Windows 10 PC, a Sony Smart TV and a Minix Neo x8-h plus. I store all my media on a NAS and use SQL to manage the library across the devices.

On the PC and Minix I have Kodi set not to auto upgrade; sadly I forgot to switch this functionality off on the Sony TV. The Sony has automatically upgraded to Kodi 17 and created a new SQL database. However the library no longer syncs with the other two devices. Unfortunately due to the minimum Android requirements of Kodi 17 and Minix’s ability to upgrade the Android version on the Neo x8-h, it is very unlikely that Kodi 17 will run on this device.

As an aside, why does Kodi need to create a new SQL database for each version of Kodi?

Second aside – where can I find a comparison of Kodi 16 vs 17, so I can see the benefits to make decision to upgrade and replace “out-dated” hardware?

My primary question is, what is the quickest and simplest way to downgrade the Sony TV back to Kodi 16? Where can I download the .apk? Is it possible to install the .apk and expect all my original Kodi 16 settings to remain after this process?

Regarding the last question, I concede not difficult to manually return to the original setup by simply overwriting the “userdata” folder with its original; perhaps I don’t even need to do that as the existing userdata folder on the Sony TV already has this?