[NikolaeVarius]

I agree. This is a perfectly appropriate notification. Its impossible to design systems to be beholden to everyones feelings.

[Animats]

Yes. Now a bad response would have been: "A vacancy has been detected. As you are now a single person occupying a double room, you will now be billed at the higher single-occupancy rate for a double. Payment must be made by the end of the month."