Having difficulty getting the cart to break up an order into separate shipments automatically if there is a free colour chart so the free postage does not apply to the other items in the cart if they are less than £75. Sounds like it is possible though @paul2009?
Purchases with multiple fulfillment profiles
If customers check out with multiple products that have different fulfillment profiles, their purchase may be split into separate orders, one per shipping option they choose at checkout. If there is no common, least expensive fulfillment option available, they need to select a different shipping option for each product. However, even if there is a common option, they can select different fulfillment options based on their shipping needs.
If a purchase is split into separate orders, the customer will only check out once, but you’ll fulfill orders from the purchase individually in the orders panel. Customers will receive multiple order confirmation emails, and in sales analytics, your average order value may decrease because your revenue will be divided by more orders.