GCM sending duplicate push notifications even though notifications delivered successfully on device

[amits]

Hello,

Since last 12 hours, GCM is sending duplicate copies of push notifications sporadically after few mins even though they are successfully delivered first time on device. I have set the delay_while_idle=false. This was working perfectly before last 12 hrs. Is anyone else seeing the same issue?

We haven't seen any specific pattern on OS version upgrade, etc.