For rush orders, you must assign an immediate allocation type to the sales document. The system then tries to allocate a requirement immediately when a sales document is created or modified. A requirement can only be successfully allocated if there is sufficient stock (for example, physical stock or stock against future receipts). It is assumed that only those goods are available for sales that actually exist in the warehouse. The stock situation remains clear. You can tell the customer directly whether the ordered goods are available in the requested quantity. Note that the document must contain all delivery-related data when it is saved. If it does not, the allocation is cancelled and the requirement cannot be delivered immediately.

You can assign an immediate allocation type to a sales document in Customizing under   Logistics - General SAP Fashion Management Order Allocation Run (ARun) Cross Applications Sales Document Handling Maintain ARun Types for Immediate Allocation .