2017-06-01, 03:28
The first device you upgrade to 17.3 will upgrade/migrate your MySQL databases to the new database version which won't be visible to your devices running older versions of Kodi, so you'll then need to upgrade those Kodi devices to the same Kodi 17.3 version in order for all your devices to be using the same database version. You should not need to rebuild your library provided the database migration is successful (it usually is).