I tried using the Dexcom app, which gave a good connection to the 8H sensor but like you I wanted to use xDrip+
So I did use the Dexcom Share info for the xDrip+ source. This DID work, after a fashion. Certainly more reliably than connecting directly to xDrip+.
Unfortunately, if you now consider the path of the data, you will realise what a nightmare this is.
Any hiccups in your Internet connection or your Bluetooth signal and you are right out of luck.
The Dexcom help desk said my phone was not suitable and also said that I needed to downgrade my phone from Android 9 to version 8.
Unfortunately for me I also had issues with my skin rejecting the sensor. Add to that the HMRC taking another £250 a month off me for their mistake, made me realise that this was not going to happen.
As for restarting sensors. If you remove the 8H transmitter for 15 mins, then put it back in, you can Restart a sensor again using its own number.
I went back to using a Libre/MiaoMiao hope this helps.
Regards
Chris Eaton