Create a VPC
Create a network in VPC
Create a VM in network in VPC
Shut down VM
Observed: Something cleans up the unused network in the VPC, removing the guest network nic from the VPC router.
Observed: New nic is allocated for VPC router
Observed: Router shows both old and new nics.
We need to either avoid cleaning up these nics when the aren't used, or avoid showing them whenever a VPC/router is queried for nics.
As a bonus, I've occasionally seen vpcs fail to be deletable. It seemed to be because some of its nics had no broadcast URI (the removed ones), and a NULL pointer was thrown.