Comment 3 for bug 1605343

I want to expand or shrink Public or Provider network CIDR (and thus range) without re-allocating all IPs.

Adding new Subnet and deleting old one is not working until all Ports are updated to use address from new Subnet. Also, there is no way to set overlapping Subnet this way.

I'm aware of the fact that updating IPv4 addresses on VMs is barely possible. However, Neutron allows it with port-update mechanism, so I see no difference between allowing operator to change Fixed (Floating) IP for single port, and for many ports.