I can think of a much simpler expression.
Time and TimeStamp fields internally store the value as an integer that represents a value in seconds.
Time fields store the number of seconds since midnight and TimeStamp fields measure the elapsed seconds since Midnight of 12/31/0000.
Thus, you can use this expression to check to see if the time is between 8:00 AM and 7:00 pm (19:00 hours).
Let ( T = Get ( CurrentTime ) ; T > ( 8 * 3600 ) and T < (19 * 3600 ) )
I put in the multiplication to show how the math works. You can use this expression to get the same results:
Let ( T = Get ( CurrentTime ) ; T > 2880 and T < 6840 )
haha fair enough, much simpler indeed. Thank you Phil!