[2.2] dhcp-acquired IP address of a node in rescue mode disappears from cli output and web ui

1) Sent a node to rescue mode

2) An ip address for it was present for a certain time with "DHCP" in the IP address column.

3) I am able to connect and use the node in rescue mode

4) After some time (not clear what amount, but probably > 10 minutes or even more) the address is removed from the web ui and 'auto assign' is placed in the respective column

5) I can still ssh into the node

original output:
http://paste.ubuntu.com/24920519/

After a certain time

ubuntu@maas:~$ maas maas machine read node-092986ae-5daf-11e4-93f3-525400a6ab07 | jq '.status_name'
"Rescue mode"

ubuntu@maas:~$ ssh ubuntu@10.232.0.108 'ip -4 -o a s'
1: lo inet 127.0.0.1/8 scope host lo\ valid_lft forever preferred_lft forever
2: enp4s0f0 inet 10.232.0.108/21 brd 10.232.7.255 scope global enp4s0f0\ valid_lft forever preferred_lft forever

# no address in the 'machine read' output
ubuntu@maas:~$ maas maas machine read node-092986ae-5daf-11e4-93f3-525400a6ab07 | grep 108 ; echo $?
1

---

ubuntu@maas:~$ maas maas version read
Success.
Machine-readable output follows:
{"subversion": "bzr6054-0ubuntu1~16.04.1", "capabilities": ["networks-management", "static-ipaddresses", "ipv6-deployment-ubuntu", "devices-management", "storage-deployment-ubuntu", "network-deployment-ubuntu", "bridging-interface-ubuntu", "bridging-automatic-ubuntu", "authenticate-api"], "version": "2.2.0"}

---

Screenshots are attached with the web ui output.