I am aware of the 29:59 or 4GB limit but I can't get the camera to record longer that 10ish mintues. I have a Sandisk Extreme Class 10 32gb card that does 80MB download speed. I have adjusted all the video quality settings in the camera so that I don't reach the 4GB limit as fast but I still only get to 10ish minutes and it quits.
It sounds as though you had either hit the 4GB recording limit or there is another reason why it won't record to the stated time. An increase of the camera's internal temperature may cause movie shooting to stop before the maximum recording times shown in the manual. The clip size is also dependent on the subject and the increase in the camera's internal temperature.
If this is an urgent technical support matter then you can get ahold of us through Canon USA.