In the final interview they ask you questions all relating to customer service, such as "Tell us how you delt with a difficault customer, and what was the outcome"...Basically they just want to see how you deal with people in different situations, and weather you are a people person i guess. They said to us that it dosnt matter how many people they take from the final group, they have no limit, its just who they think is suitable for the job...And it wont be a drama if you can't start for two and a half monthes, my friend who also got thru with me isn't starting until a couple of monthes after as she had work commintments...Good luck!!!
Oh, and regarding the weight issue, I think it said your BMI had to be under 25 on the medical forms...But it could be over if your weight looked good on your height.