I added a fake token for testing, and I am seeing this in the logs:

Processing [MismatchSenderId] error code from GCM response, for registration ID: [APA91bGVJjnqOASDasFAFDSFASDSFADFSDAAFSDFDSmU5NyLGOsiumWyN62BjE8FCVvYscnKzZrokIYadsadsasADas_s45cUnxdJEVrBokHX5k0fewfoV2JD17GUx5s5]

I was guessing that we do remove these tokens, but no... IMO this should be fixed that, no ? 

-Matthias

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