anchor.diff:          ContentId : string
           MessageLockId : Guid
           ParentJobId : string
  -        Offset : int64 option 
  +        BatchIndex : int option
           TargetWorker : string option
           DeliveryCount : int
           DequeueTime : DateTimeOffset
  
positive.code:                 let affinity = tryGet Settings.AffinityProperty
                  let deliveryCount = message.DeliveryCount
                  let parentId = fromGuid (message.Properties.[Settings.ParentTaskIdProperty] :?> Guid)
                  let streamPos = tryGet Settings.StreamOffsetProperty
                  let lockToken = message.LockToken
                  let body = fromGuid (message.GetBody<Guid>())
                  let jobId = message.Properties.[Settings.JobIdProperty] :?> Guid
  
negative.code:                     ConfigurationId = config
                      MessageLockId = lockToken
                      ParentJobId = parentId
                      BatchIndex = batchIndex
                      TargetWorker = affinity
                      DeliveryCount = deliveryCount
                      DequeueTime = dequeueTime
  