calculating Turn around time

Hi,

I've browsed the net searching for a solution to my problem and found one solution altough not entirely what i was after, but it was very close. It was provided on another forum, of which i'm not a member.
http://www.ozgrid.com/forum/showthre...t=68277&page=4

I have a TAT target of <= 2hours, however this is complicated by weekends, holidays and jobs received after working hours and on weekends.

I've attached the file, which contains detailed information about my problem. Appreciate if you can help me with some functions or code to solve my specific problem. i'm a relatively average excel user and possess some basic knowledge on functions and nothing on vba codes.

I've tried to be as detailed and informative as possible, however it's quite possible for me to have missed out providing some key information, please let me know and i shall provide. Appreciate your help on this query.
Kind regards,
Ram