I need a formula to help in the distribution of the quantities by months according forecast sales and When the quantities of batch ends jumping to the quantities from the next batch to make up

Dear ,

I hope you are doing great

I have a small problem I hope to find a solution for the purpose of facilitating the work, I have two product A&B and there quantities available  for sales in the store , the quantities categorized according batch no .

As well,  I have information about what are the expected quantities of sales on monthly basis  of each product.

Now I need a formula to help in the distribution of the quantities  by months according  forecast sales and  When the quantities of  batch  ends  jumping  to the quantities from the next batch  to make up the shortfall.

For more clarification i have enclosed my exercise , Please see the attached

Your  cooperation is highly appreciated

Thanks
my-exercise.xlsx