Can't start deploy for selected nodes

I've added node to a cluster and provisioned it. But after trying to start deploy by a separate command, nothing is happening:

fuel node --node-id 1 --deploy

The message, appeared in logs:

2016-06-15 15:25:14.493 ERROR [7fe36436c880] (manager) Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/nailgun/task/manager.py", line 58, in _call_silently
    to_return = method(task, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/nailgun/task/task.py", line 230, in message
    objects.NodeCollection.lock_nodes(nodes)
  File "/usr/lib/python2.7/site-packages/nailgun/objects/node.py", line 1243, in lock_nodes
    instances_ids = [instance.id for instance in instances]
  File "/usr/lib64/python2.7/site-packages/sqlalchemy/orm/attributes.py", line 237, in __get__
    return self.impl.get(instance_state(instance), dict_)
  File "/usr/lib64/python2.7/site-packages/sqlalchemy/orm/attributes.py", line 578, in get
    value = state._load_expired(state, passive)
  File "/usr/lib64/python2.7/site-packages/sqlalchemy/orm/state.py", line 474, in _load_expired
    self.manager.deferred_scalar_loader(self, toload)
  File "/usr/lib64/python2.7/site-packages/sqlalchemy/orm/loading.py", line 610, in load_scalar_attributes
    (state_str(state)))
DetachedInstanceError: Instance <Node at 0x2220ed0> is not bound to a Session; attribute refresh operation cannot proceed

The importance of this bug is critical because:
1. In large OpenStack environment, it is important to enable our customers to run deployment only on subset of nodes without running deployment for the whole cluster. This allows our users to incrementally deploy large & complex environment. This bug breaks this functionality completely without workaround.
2. This is a regression comparing to previous releases, it breaks feature which was implemented in Fuel 4.0 [1] and was available via CLI since this time.
3. In Fuel 9.0 we extended this functionality by adding support of this feature on UI, see [2]. This feature is also broken.

RCA:
1. This bug was introduced by https://review.openstack.org/#/c/314701/ in attempt to fix https://bugs.launchpad.net/fuel/+bug/1569859.
2. This bug was not detected neither by BVT nor by SWARM because of another issue in 9.0 mos repos - missing uwsgidecorators package, see https://bugs.launchpad.net/fuel/+bug/1572998

References:
[1] https://blueprints.launchpad.net/fuel/+spec/nailgun-separate-provisioning-and-deployment-handlers
[2] https://specs.openstack.org/openstack/fuel-specs/specs/9.0/allow-choosing-nodes-for-provisioning-and-deployment.html