when editing a host, while a proxy was reporting on a conflict the following was observed in the log, but nothing in the UI

2015-08-18T14:36:12 [app] [I] Failed to save: 
2015-08-18T14:36:12 [app] [I] Redirected to https://foreman/hosts/fqdn/edit
2015-08-18T14:36:12 [app] [W] ProxyAPI operation FAILED
 | ProxyAPI::ProxyException: ERF12-4395 [ProxyAPI::ProxyException]: Unable to retrieve DHCP entry for 10.35.27.10 ([RestClient::BadRequest]: 400 Bad Request) for proxy https://proxy:8443/dhcp
 | /home/foreman/git/foreman/lib/proxy_api/dhcp.rb:53:in `rescue in record'
 | /home/foreman/git/foreman/lib/proxy_api/dhcp.rb:43:in `record'
 | /home/foreman/git/foreman/lib/net/dhcp/record.rb:43:in `conflicts'
 | /home/foreman/git/foreman/lib/net.rb:24:in `conflicting?'