I'm in the same boat as you, OP. I got a 950 DS in late January and Notification Center and email notification pushes are inconsistent on it. Texts, calls, and Calendar notifications work, but not the rest. It did work well the first week, but wonky ever since. The longest periods of time I can get consistent push notifications from all, since that first week, is about 12 hours. I've tried various combinations of of resetting, rebooting, uninstalling, etc (on the Band 1 and phone), but no dice.