Tie the basket to the week it can be collected
Start with representative baskets, the units customers choose and the collection dates the shop publishes. Decide whether each basket has a fixed contents list or approved choices, and what a saved selection means after that list changes. A customer should be able to tell which week a request concerns before confirming it. Keep the current offer separate from a previous basket in order history so a convenient repeat action still leads to a deliberate selection.
