Currently the two QueueItemAuthenticator implementations in this plugin implement authenticate(Item) but they should also implement authenticate(Task). The fallback implementation works, but using a somewhat scary trick. Better to override it to do what you need. Implies that AuthorizeProjectStrategy also needs an authenticate(Job) method taking no Queue.Item. (TriggeringUsersAuthorizationStrategy is the only one to actually use this parameter; for that strategy, authenticate(Task) must return null.)