When enabled, Instore Pickup looks at your Shopify shipping rates for the order routing location and routes the order to that location, regardless of the inventory.
Set Pickup In Store to On. Set the Instore Pickup prefix (i.e. Prefix "Instore Pickup at " would work for shipping rates titled "Instore Pickup at New York" and "Instore Pickup at Los Angeles"). Each instore pickup shipping method must be formatted with the same prefix and end in the location name as defined in Channels (you can find your location names in the Store Priority List on the Multistore tab).
Setup a shipping rate in Shopify for each location you would like to support Instore Pickup. When the shopper selects that shipping rate for their Order, the Order will be routed to that location regardless of whether inventory is available.
Instore Pickup Routing Example
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