Comment 1 for bug 1639577

Attached to issue #1632362 is a custom build of juju with changed locking semantics. It uses juju/mutex instead of file based locking, so stale lock files are not possible. It also has a longer timeout and no exponential back off so should be less liable to lock contention.

    https://bugs.launchpad.net/juju-wait/+bug/1632362

Please try that version of juju if possible and see if it appears to fix the issue. If there's no feedback by Monday (I'm off Friday) I'll snap it up to make it easier to try. This version is based off the 2.1 branch. Porting the fix to 2.0.x is trivial as it's just changing the dependency to a newer version of juju/persistent-cookiejar where the change is made.