WNS notification - receiving 404 even on valid token

Question

I am trying to push notifications to my windows app via WNS,

I get a 404 response everytime.

I have verified that the Channel URI is valid, because every time I launch the app, I get the channel URI and use that immediately for testing.

Here is the curl call I make

curl -i -d "<tile><visual><binding template='TileSquareText01'><text id='1'>tile one text</text></binding><binding template='TileSquareText02'><text id='2'>tile two text</text></binding></visual></tile>" -H "Authorization: Bearer EgAeAQMAAAAEgAAACoAAFQOHLfF3CMYK/IUs8MgTUFoS9vwOM4AFavJ3TLGAczjxBJNm02+rMlWFGYNWAefkuCw/Qg62++O+5GdrLRqQCdBSSI+cZPPXwOKk6lagOLDXNzd41hPMG9/NYi/Li1dHddMLLkPVWuZ6Te+t1ofOeL30PDA9p8JVEVDAX/CfLXGNAFoAjQAAAAAAL+oNSH9RuFB/UbhQ60gEAA8AMTIzLjIwMS4xMzUuNTMAAAAAAF4AbXMtYXBwOi8vUy0xLTE1LTItMTIxMTkzNzMyNS0yNTg0NzczMzMzLTE1ODE1OTA0OTYtNDE4NTk0OTY5OS0yNDEwMjc4ODgzLTM4NjU2MTI0NzAtOTM5MDAzNTk0AA==" -H "content-type: text/xml" -H "content-length: 190" -H "X-WNS-Type: wns/tile" "https://sin.notify.windows.com:443/?token=AgYAAAA/Bcry6hlYw8kOU5f4LHaS+dycP7UxcsT45eUcNlxfznxCltMK3emgIsHRAiRUk1X5VnQ0h0FC7fbOno+QI5aqUt2Q05foUg+XYeFvIcdsp6wwoMJ8VEjyOBzcT+z1JNM="

I get the following response

HTTP/1.1 404 Not Found
Content-Length: 0
X-WNS-MSG-ID: 1FD852615FA1E9DA
X-WNS-DEBUG-TRACE: SINWNS2012431
Date: Fri, 30 Nov 2012 06:57:46 GMT

I've checked the headers are all correct, test this by placing a wrong header and getting 400 Bad request instead.

Here is my app code for getting the Channel URI

get_channel_uri :function(){
    var channel;
    var pushNotifications = Windows.Networking.PushNotifications;
    var channelOperation = pushNotifications.PushNotificationChannelManager.createPushNotificationChannelForApplicationAsync();

    return channelOperation.then(function (channel) {
        if(channel.uri){
            // send to server
        }
    },
    function (error) {

    }
    );

}

Any ideas what am I missing?