@YIK I haven't done Shopify development in a while. All I can suggest is you use the GraphQL API as you will have less requests compared to the REST one.

Following on from my previous post above - the reason fulfillmentOrders wasn't showing up for me was because "Merchant managed fulfillment orders" permission wasn't set.  So you can now get the assigned location in fulfillmentOrders before the order ...

I've setup a development store with 2 locations where I'm making test orders. Looking at the orders in admin I can see it is assigning locations to orders depending on where the inventory is located. I'm using the GraphQL API BTW. Orders that haven't...