Reply To: selected time interval is different than actual reserved

The standard if no departure field exists is “arrival + 1 billing unit”. I’ve changed that to arrival for the future, hopefully this change wont break much other forms.
However, to fix your problem now you can add a hidden units field with the value 0. But I would suggest using the [units] field instead of the to hour and minute to make the selection easier for your guests.
Regards