This library has worked very well for us, but since it's no longer maintained and my projects are dropping RxSwift, I created a Combine wrapper for CoreBluetooth, written with testability in mind.
If anyone is interested, this is the repo:
https://github.com/teufelaudio/CombineBluetooth
My intention in sharing this is possibly helping other orphans of RxBluetoothKit and I wouldn't do this if there was some hope in the original repo.
The new library is not yet battle tested, but we are investing a lot of time to make it as stable as possible quickly.