I looked at the logs on my HDHomerun devices and there was some tuner reuse, but again I think that’s the HDHomerun helping it out. But there was also a case where it had a station tuned and that it reused once already but then had the other device tune to the same channel
Also an interesting part was where Plex was recording a show of a lower priority while a higher priority show was waiting to start and there was a free tuner waiting on the other device. When the show ended it switched the tuner to the higher priority show. This isn’t how I would expect the priorities to work