upstreamErr(con, err)
				return
			}
			select {
			case con.deltaResponsesChan <- resp:
			case <-con.stopChan:
			}
		}
	}()

	go p.handleUpstreamDeltaRequest(con)
	go p.handleUpstreamDeltaResponse(con)

	for {
		select {
		case err := <-con.upstreamError:
			return err
		case err := <-con.downstreamError: