Comment 8 for bug 1798904

i believe this was fixed by
https://github.com/openstack/os-vif/commit/d291213f1ea62f93008deef5224506fb5ea5ee0d

when isolate_vif=True we will plug the interfaces on the dead vlan 4095
that will prevent the port form sending receiving packets until it is moved by the l2 agent to the tenant vlan.

i have not recently check this case specifriclly so its not clear if its resolved but i belive it should be. that chage was released in december 2018 https://github.com/openstack/os-vif/releases/tag/1.13.0 as part of the parent issue https://bugs.launchpad.net/neutron/+bug/1734320

we should still validate this to confrim before we update this to fixed release.