I was wondering if an airliner was instructed to line-up on the runway ("line-up and wait"), will the park brake be used or will manual braking be used (pedals) during the wait until the take-off clearance is given? Same for holding short the runway before line-up / take-off clearance? Does it make a difference which brakes are used in the first place?
Just toe brakes. Typically the instruction between line-up-and-wait and clearing for takeoff is very short, maybe ten seconds. In simpler aircraft, the parking brake just "pinches" or closes off the brake fluid line to keep the wheel brakes held, but in the fly-by-wire airliners, the parking brake just clamps the normal wheel brakes as if the toe brakes were held.