Replace items during the fulfilment - and access to the replace alternates during this step

We usually replace items when we don't have any on stock for a substitute, usually it's something we find out when we are fulfilling orders. When the option the add alternate is very useful, it can only be used for draft orders. Once authorised, and partly fulfilled you need to undo the whole order fulfilment to replace the whole order and then authorise all past fulfilments and invoices again. This could cause errors and it could be time consuming.

It makes send the replacement of the stock could take place during fulfilment without having to undo the whole order.

I am pretty sure this wouldn't be an isolated issue at my company and lots of companies are struggling with this.