I would not rule out a custodial sentence this time, after all you have not learned your lesson and the fines have not been paid. A suspended sentence is possible with the condition that you will go to prison if you do not pay off the previous fine and stay out of trouble.
This is going to depend on the magistrate on the day , you need to be sure to tell the court that you are really sorry and this time if given another chance you are determined to stay out of trouble and repay the damage caused.