I have just started in VarAC using my IC-7300 and a Windows 10 PC. It is a very interesting concept to have a link which is correcting across the low power links I am licensed to make. I am moving here after trying FT8 and JS8Call.
I contacted a german station for my first QSO using this system yesterday and enjoyed the interaction. I had a problem with how to discern the 'over' and I tried using the 'btu' but with no real success. I like to type several quite long sentences and use CR/LF as the end of each one. I think we clashed at one point and I lost some data. Still it was a good QSO.
At the end it was a bit too abrupt. The other station sent nice comments ending with 73s and goodbye then .... the link just died. I couldn't reply with my end of QSO comments.
VarAC then tidied up and the disconnect was complete. I was left feeling a bit confused.
I'm sure there must be a better way to finish. The software that handshakes could easily have a flag to say first station end, then the second station could see that and have one more message allowed. It would be much more polite.