Allocating Expiring Product to Requirements with dates specified

[Kristinbell]

Supply Chain Planning Issue: I'm having trouble coming up with logic to allocate product to requirements for specific dates but taking into account when the product expires. I mocked up an example attached where I'm stuck. I need to use the product in order (by batch ID) and allocate it to the requirements. But I cannot use the product when it hits the "Unusable Date". If the "Unusable Date" and the "Requirement Date" are in the same week, that's fine though. Any thoughts on how to do this logic across a large set of possible SKUs?

[shancmiralles]

hello  @Kristinbell ..

im a bit confused with your description.. 

i downloaded your WF in which tool are you stuck? can you also provide on output on how your sample data should look like? 
(sorry im a very visual person)
thanks!