Need to find correct Formula in Excel- Urgent

Hello,

Received one issue on 29-Sep-11, the turnaround time to solve this issue is 6 working day. In my case A1-9/29/11 and TAT for its closure of the particular issue is 6 working Days i.e B1- 6, Now i need to find out what is my closure date or the escalation in days- which means how many days are in my hand to solve the issue. Kindly help on urgent basis. if i will use "networkdays" then I must have the closure date however that itself is the issue to get the correct closure date , where sunday has to be excluded. Hence after using the correct formula my answer should come as 1 , which means as on 07-Oct-2011 my issue got escalated for one day.Would appreciate if anyone can solve my issue as I am trying to get the correct way out since 3rd Oct 2011. Thanks.