Why can't you have two versions? Personally, I've got everything from 2015.3 to the current version, one from each series. The program files are really not that large, so they don't take any significant space.
And having one that you know is 'stable' is always wise. You can always get work done.
The BlackMagic plugin is apparently continually problem-prone. I gave up on it and bought the Autokroma BM-RAW plugin for Premiere & Ae. It always just works and besides that, gives options for presets and things the freebie from BM doesn't.
And they offer the best help/support for BRAW issues no matter whether you use their plugin or the BM one.