In reply to Peter Grafton.

Hi Peter,
We will have 2 new SKUs available for 3850 family (24 and 48 ports), an those will be stackable with the existing 3850. The 48 ports version will be orderable in April. This functionality won't require any specific license.

For the 4500E, we will have a new linecard available soon, and you will be able to use it with your Sup7E/7L-E.

Regards,
Samuel