Restaurant takeout orders: customers want to order once for two separate pickups

[aloeroot1]

Thanks in advance for your help. My clients run a takeout restaurant through Shopify, where they offer pickup three days a week.

They have customers going in to order for Wednesday and Saturday (or Wednesday and Thursday, etc.) at the same time. They want to do it in one transaction.

Can anyone suggest an angle of approach for this? Right now they offer a choice of locations for pickup (which changes based on the day), but that's a radio button group that applies to the entire order.