Ability to Allocate Stock between Order Authorization and Pick (after an Order has been Authorised, before Pick started)

For some businesses, there are business workflows where they do not want to allocate stock when initially authorizing the Sale Order, and then later would like to be able to allocate stock before the Pick step is completed.  This happens in a variety of situations including orders to be filled at a later date and orders which require prepayment before the business will allocate stock to the sale. 

These businesses use the General Setting "Make stock allocation optional" set to Optional and choose "Don't allocate stock" option when Authorising the sale.  See Screenshot #1 below.  Later, when the order is ready for fulfillment processing, they want to be able to allocate stock in CORE, but are not ready to specifically pick the stock.  In some ways it is similar to the General Setting feature "Make stock allocation optional", but delayed choice of allocating stock.

Envisioning this feature, one way to do it would be to add an "Allocate stock" button to the Order tab for a Sale Order.  This button would only appear for Simple Sales which has been set to "Don't allocate stock".  See Screenshot #2 below.

Screenshot #1: Initially Authorise with "Don't allocate stock"

Screenshot #2: Allocate Stock button present for Simple Sale Order which has been set to "Don't allocate stock" earlier