unpack() in AppleNotificaion produces a notice

[kix]

Here's the log output I get:

[2016-08-12 08:33:46] php.DEBUG: unpack(): Type C: not enough input, need 1, have 0 {"type":2,"file":"vendor/richsage/rms-push-notifications-bundle/RMS/PushNotificationsBundle/Service/OS/AppleNotification.php","line":260,"level":28928}

[richsage]

Is this reproduceable? A bit of research suggests it may be related to problematic data coming back from the remote server once in a while, that's all...