Edit the Location a Sales Order will be fulfilled from on existing Sales Orders.
The Sales Order location cannot be changed if there are active subdocuments against it. (e.g proformas, delivery notes, etc)
If present, the subdocuments would need to first be made inactive.
The Sales Order populates with the default Location from your Customer record
You can only select a Location that has previously been set to fulfil your Sales Orders from in your System Settings.