Huawei Ascend P7: Problem with Push Notifications I've just purchased 2 brand-new Huawei Ascend P7 phones and have problems with both: The Push Notifications do not work properly: messages come in delayed, sometimes only when I enter the corresponding app. 

This is not restricted to a specific app, and occurs on both Wifi and mobile data. I have given all apps push notification permissions within the Notification Manager, I have also disabled Smart Power Saving Mode and enabled always-on mobile data (hope that helps keeping the GCM connection alive).

One of my phones already received the new system update to P7-L10V100R001C00B121SP01, the other one is still on L10V100R001C00B116SP3.

I've googled a bit, this seems a common problem with those P7s. Any ideas?
Make sure you've turned on Datasync in Settings
Use https://play.google.com/store/apps/details?id=com.andqlimax.pushfixer to set notification heartbeat interval
If nothing helps, factory-reset your phone
Check if the same problem appears on both phones, if yes, try a different telephony company