Formula for cashflow

[Ducklings23]

Hi all, I am putting together a cashflow and I want to be able to split payments to allow 50% on order of an item and the remaining 50% on delivery, which is to be 3 months after the order date. I have the order date column, the total cost of the item and then all the months of the contract duration to the right. The cost of the item is escalated yearly by an inflation amount which is in my spreadsheet. I want to basically say when there is an order, show 50% of the total cost in that month and 50% three months later. If the later payment goes into the next financial year, then don't inflate, just be 50% of the cost at order. Hope that makes sense! Thanks in advance.