Using Lookups & IF Queries Together?

I'm currently working on a side project for work that I believe will save many man hours as at the moment we're using paper and calculators!!! I'm scheduling buys. I've worked out formulas and formats to show how much we should buy and how they should be split (for example for UK purchases we buy x amount and split it 10% 90%). However, the dates of delivery are different. See below:

PORT L'poolPORT HKPORT Portsmouth
1.113-Aug-1206-Aug-1230-Jul-12
1.210-Sep-1203-Sep-1227-Aug-12
2.103-Sep-1227-Aug-1220-Aug-12
2.201-Oct-1224-Sep-1217-Sep-12
3.124-Sep-1217-Sep-1210-Sep-12
3.222-Oct-1215-Oct-1208-Oct-12

Campaign 1 first buy (1.1) I know that my product is sailing from port HK. Therefore I want it that in the 'delivery date' cell, it returns 6/aug/12 (that's the first lot of 10%, and underneath it returns 3/sep/12) which the remaining 90%...2.2).

However, both the campaign number AND port options are variable (using a data validation drop down list). In effect meaning if I choose campaign 2 instead of campaign one, it'll return the dates 27/aug and 24 sep....if I then change the port to Portsmouth, the dates will be 20 aug and 17 sep.

I've attached a quick view of the schedule I've created. The yellow cells are where I want the dates to be returned.

ScheduleEX.jpg