Create two formulas to encompass the time you want:
@from this time
datetime(year({?Date}),month({?Date}),day({?Date}),10,00,00)
@to this time
datetime(year(date(dateadd("d",1,{?Date}))),month(date(dateadd("d",1,{?Date}))),day(date(dateadd("d",1,{?Date})))
,04,00,00)
Then in your selection expert:
{datetime.field} in {@from this time} to {@to this time}
Above combination will give you transaction that have occured from 10AM to 4AM the next day. Mike