If your project uses neutron callbacks, please read on. As we discussed during the PTG [1] in the "Cross project related topics" section, we'll treat the adoption of the new payload style objects as we have been with other lib impact changes. That said, the first (and easiest) set of patches are queued up [2]. All sub-project patches in [2] should depend on the neutron change [3] and ideally they can be ready to land when we pull the trigger on [3]. If folks could help with this reviewing effort, it'd go a long way in making this transition smooth. Thanks [1] https://etherpad.openstack.org/p/neutron-queens-ptg [2] https://review.openstack.org/#/q/message:%22use+new+payload+objects%22 [3] https://review.openstack.org/#/c/474213/