[Katello] Hypervisors with name == UID and hostname after changing virt-who to use hypervisor name

I've changed my virt-who config to send hostname as the hypervisor id (was
previously sending UID to foreman/katello).
The esx hosts are showing up in content hosts as their hostname now. I
deleted all the UID instances of the esx hosts and reassigned the
appropriate licenses.
But the hypervisors keep appearing with name==UID (as well as with
hostname). I've checked the virt-who logs (rhsm.log) and this is only
sending hostname.
Checking foreman production.log I can see the hypervisors being added here
by UID in the following log entry:

2016-08-05 10:26:23 [app] [I] Started GET "/rhsm/status/" for at 2016-08-05 10:26:23 +1200

2016-08-05 10:26:23 [app] [I] Processing by
Katello::Api::Rhsm::CandlepinProxiesController#server_status as JSON

2016-08-05 10:26:23 [app] [I] Completed 200 OK in 123ms (Views: 0.5ms |
ActiveRecord: 0.0ms)

2016-08-05 10:26:23 [app] [I] Started POST
"/rhsm/hypervisors?owner=123456&env=OrgName" for at
2016-08-05 10:26:23 +1200

2016-08-05 10:26:23 [app] [I] Processing by
Katello::Api::Rhsm::CandlepinProxiesController#hypervisors_update as JSON

Followed by the json parameter list with all the hypervisors (by UID) and
guest UIDs.

Is there something is candlepin that I need to clear/refresh to make it
aware that the hypervisors are now referenced by hostname. This is
impacting by licensing as some of the guests are shown as being on the
hypervisor identified by UID (which hasn't got the datacenter license
applied to it).

Version details:

katello 3.0.2

foreman 1.11.4

virt-who 0.14-9.el7_2.1


RHEL 7.2