Modules & VBA :: Calculating Elapsed Time Within Time Period

I have a working dB which can calculate a shift duration and sum total all shifts worked within a period for the purpose of producing a labor report for payroll. I have successfully used the DateDiff function and converted the minutes to HH:MM on my form and reports. Now I want to calculate elapsed time for a specific period within a shift, I'll call it OtherHours and I am aiming to calculate a portion of time that meet the following conditions below. I am using field names of [PunchIn] and [PunchOut] and both are of type General Date.

IF [PunchOut] ISNOT Saturday,Sunday
EXIT FUNCTION
ELSE
IF [PunchOut] ISNOT Between Midnight and 0559 hours
EXIT FUNCTION
ELSE
DATEDIFF ("n", <MIDNIGHT>, [PunchOut])

My thoughts are to solve the DateDiff portion and then figure out how to apply the conditions within the IF statements.