We are aware of push delivery delays for all platforms which started from 14:35 GMT up to 14:47 GMT approximately. We are currently investigating the issue to understand what happened. We identified a problem with one of our internal service after a sudden load spike which triggered a cascading failure and resulted in the processing time for new campaigns increasing dramatically. This failure caused delays of up to 15 minutes before new campaigns started to be processed. We are currently taking steps to better mitigate load spikes so that this won't happen again.