Amphora instance deleted while nextworks are being attached

While running rally-openstack the Octavia.create_and_list_pools test failed.

It looks like the amphora instance was created and destroyed before networks were attached. Note the timestamps below.

octavia_1/var/log/octavia/octavia-worker.log
2020-05-25 16:29:38.091 468740 ERROR octavia.compute.drivers.nova_driver [-] Error attaching network None with ip None and port 6ee0f7ca-442f-4a81-914a-e7e38b920aca to amphora (compute_id: cf46ffd6-c9d5-4abc-9c10-c0a7ad1ae363) : novaclient.exceptions.Conflict: Cannot 'attach_interface' instance cf46ffd6-c9d5-4abc-9c10-c0a7ad1ae363 while it is in task_state deleting (HTTP 409) (Request-ID: req-fb1e9688-a6ec-4f7a-bfb3-91fe89a8939c)

./14/baremetal/var/log/nova/nova-compute.log has
2020-05-25 16:29:04.136 830216 INFO nova.virt.libvirt.driver [-] [instance: cf46ffd6-c9d5-4abc-9c10-c0a7ad1ae363] Instance spawned successfully.

but then destroyed

2020-05-25 16:29:38.826 830216 INFO nova.compute.manager [req-c35e4d9c-abf7-4965-845c-8c1c35064c6d 89b893e8168349069916e38b0a137c6a a1db1f9704484ade86fcd877291f1ca5 - 05bf33a261f743f0a5290752983ad30b 05bf33a261f743f0a5290752983ad30b] [instance: cf46ffd6-c9d5-4abc-9c10-c0a7ad1ae363] Terminating instance
2020-05-25 16:29:39.247 830216 INFO nova.virt.libvirt.driver [-] [instance: cf46ffd6-c9d5-4abc-9c10-c0a7ad1ae363] Instance destroyed successfully.

The bundle and logs are available by following the link at the bottom of the Solutions QA test run page linked here:
https://solutions.qa.canonical.com/#/qa/testRun/7577bf0c-64bc-47d0-9434-68a4de32cb00