There's an option to choose Overage. If you run over a second or third time, you will be charged each time. I've gone over many times. Actually, you will get more than the allotted picture count. If you have firmware 8.0 or 8.1, you can remotely manage your picture count or runaway by turning off Delays or turning camera off.
Like RRAB58 said you will get more than your allotted amount of pics. Cuddeback's 750 images is really conservative. I paid attention to that for a while and I think you can actually get around 1100 to 1200 out of the basic package. I don't know the percentages but it seems that most cameras if they run away they usually do it out of the box.
Before you deploy them I would update to the 8.0. or 8.1 when it hits the street. Definitely sweet to have that. I had 2 cameras a couple of weeks ago that were getting some false images when it was windy from a couple of weeds that grew up in front of them. I simply logged in and turned off the daytime pics, so that I wouldn't rack up pictures and I would still get night pictures. Next time I was there I cut down the weeds and then changed the settings. I really prefer to change settings online vs the camera as it is quicker. Although not all things can be done remotely.