A while-stopped step stops its module's containers, and an apply arriving
mid-window read the stopped server as broken and recreated it running under
the step - for the store's collector, a registry taking an upload the sweep
then deletes. The scheduler now records each window under the node's state
directory before its first stop and erases it after its last start, so every
apply on the machine (daemon, reconcile by hand, installer) reports a held
container held-still and leaves it for the first apply after the window.
A window whose host died, or past six hours, holds nothing; the report says
which windows are open.