Is your warehouse HU managed or only SU managed
As a best practice we generally supply the HU related information to the 3rd party upon Post Goods Issue to delivery. In your case if you want to supply the Storage unit information then you can plan to send the Transfer order information upon confirmation of the transfer order however that is not advisable as Confirmation of transfer order doesn't mean that you are dispatching the goods at the same time or same day or it might happen that due to some reason after TO Confirmation you are unable to perform the PGI and unable to dispatch the load at all.