Calbaw, firstly - don't worry. Your car's ok
Having the electromechanical handbrake disengage when you step on the throttle is normal. It is the same in other conti cars with the same handbrake. The A6 and A4 are the same, as well as the newer Volvos (S60 and XC60). The idea behind this is so that you don't kill the electromechanical system by "dragging" it along. I know that in the Audis, for the handbrake to disengage when you step on the throttle, you MUST have your seatbelt on. The logic behind this is that since you've put on the seatbelt, if you step on the throttle to go but have left your handbrake on, it is most likely you forgot to release it so the car will automatically release it for you. If you DON'T have your seatbelt on, then the handbrake will NOT disengage on the assumption you are not ready to go yet and you stepped on the throttle by mistake. I like this on the Audi because it acts as a bit of a safety check by not disengaging when you don't have your seatbelt on.
On the Volvo, this is not the case. The handbrake will disengage when you step on the throttle, regardless of whether the seatbelt is on or off. This is ironic and disappointing given that Volvos are supposed to be the "safest" cars in the world.
I'm not sure on the F10 whether it works like the Audis in that it will only disengage when you have seatbelt on or like the Volvos where it disengages regardless. I'll go try it on mine one day but if you do get around to trying it first, do let me know