Hi @Al_Noman
Actually, Shopify doesn’t currently support automatic switching between shipping profiles based on inventory, but you can achieve this with a combination of Shopify Flow, third-party apps, or custom code.
With Shopify Flow, you can create an automation to tag products as “Preorder” when inventory hits zero, then adjust shipping rates based on tags.
Wit third-party apps, you can consider using Advanced Shipping Rules or ShipScout can help dynamically adjust shipping rates based on stock levels.