How to turn off notifications temporarily in iOS?

I was expecting an important Skype call on my iPad. I wanted to make sure there were no notifications coming through so I set do not disturb.

However I kept getting email notifications little drop-down banners that disappeared but if I left the mute switch on that is so that I could hear alerts those alerts came in full sound.

I thought the purpose of this simple do not disturb slider was so that if I wanted to temporarily just stop all alerts and I mean all alerts I could just turn do not disturb on and everything would be quiet. Further the alerts wouldn't even show up they just wouldn't come in but that doesn't seem to be the case at all.

I have the little crescent moon next to the clock in the top menu bar but that doesn't seem to stop all these notifications from coming in.

I am still on iOS 6.0.1 and will soon upgrade to 6.1 but I don't think that's the cause of this.

Any comments on what I might be doing wrong here would be appreciated. I mean it seems so simple you don't want banners sounds and alerts you slide you turn on do not disturb. BUT–It doesn't work.

Steve

30 Jan 2013