Adding a second express route to a virtual network

Hi guys, I already have an express route through a connectivity provider at a co-location facility linked to a virtual network but am looking to create a second express route and linking it to the same virtual network.

Is this just a matter of entering:

new-azurededicatedcircuitlink -servicekey <skey1> -vnetname  VNET1
new-azurededicatedcircuitlink -servicekey <skey2> -vnetname VNET1

Or do I need to go into the XML code of the gateway and do stuff in there? If so, can you provide a link or information explaining how I go about this?

Thanks.