Yep
Is there any existing plugin for that or should I write a new one?
I wrote something near for a customer because he use own multiple stores pickup
I use for this a new table with the list of pickups, added the pickup ID in the table #__virtuemart_shipment_plg_myplugin
i wrote a new module so each pickup can see own orders and change the statut in the front end. I use user group to restrict access to this module
I think it's what you need ?