I think this would work:
- Mac App Store Apps and Distribution Method: Install Automatically/Prompt Users to install and Scope to Labs
- Mac App Store Apps and Distribution Method: Make Available in Self Service and Scope to specific users.

Thanks @dmichaels . Yes but I can't see how to have two items that are xCode. If I go and purchase more licenses from Apple School Manager they just get added to the existing block. Is there a way somehow to differentiate them so I get two different items in Mac App Store Apps for a particular product?

I see your dilemma now, it only lets you add ONE instance per Application. I guess I would push out to devices first and then set it up again for Self Service.

I have multiple instances of MANY of my apps in my Jamf Pro App Catalog for this reason, and also due to site based management. If attached to the same vpp token, the two catalog items will pull from the same pool of licenses

Thanks @Sandy ! Even though it's Saturday I logged in and checked and it looks very plausible under Mac App Store Apps and then click New to add it again. I now have one just called Xcode and another called "Xcode - Auto Deploy" which I've scoped to the lab.

I haven't been adding any apps like this as they just "appear" after coming from Apple School Manager. I'll give it a go on Monday - appreciate the help!