Yes,you are right.This is happening while deleting azure,gce and ec2 subnets. Have logged a separate issue and can be track in bz https://bugzilla.redhat.com/show_bug.cgi?id=1398099.
Since the above issue is not observed while deleting the subnets, marking it as verified.However,while deleting the openstack subnet we are getting unexpected errors and this is tracked in https://bugzilla.redhat.com/show_bug.cgi?id=1397469.
Version:
5.7.0.11-rc1.20161115160629_46cf4f1
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://rhn.redhat.com/errata/RHBA-2017-0012.html