Channel API Errors

[Prateek Malhotra]

Been getting these errors all morning:

File "/python27_runtime/python27_lib/versions/1/google/appengine/api/channel/channel.py", line 238, in send_message
    response)
  File "/python27_runtime/python27_lib/versions/1/google/appengine/api/apiproxy_stub_map.py", line 94, in MakeSyncCall
    return stubmap.MakeSyncCall(service, call, request, response)
  File "/python27_runtime/python27_lib/versions/1/google/appengine/api/apiproxy_stub_map.py", line 328, in MakeSyncCall
    rpc.CheckSuccess()
  File "/python27_runtime/python27_lib/versions/1/google/appengine/api/apiproxy_rpc.py", line 133, in CheckSuccess
    raise self.exception
DeadlineExceededError: The API call xmpp.SendChannelMessage() took too long to respond and was cancelled.

I have a backend trying to communicate to frontends using the Channel API and this error is causing backend processes to fail. I've never had these issues in the past and there have been no code changes. AppEngine status dashboard doesn't list this API so not sure if its a system-wide issue.