Comment 12 for bug 1710848

AIUI the link-local subnets are only seen by "admin" style users of Openstack. If you create a tenant and give it only access to useful subnets, then we don't have the same problem with duplicate subnets.

We'll try to put something into 2.3 (bug #1710848) as a workaround, but the correct fix for modeling multiple networks with subnet ranges that can overlap is more of a 2.4 fix.