As my first attempt to do front bearings and brakes, i took off the wheel and the 4wd auto hub as described in this link

I thought of replacing the brake pads before taking the caliper out and getting to the rotor. I removed the lower slider pin bolt. But the caliper wouldn't swing open around other (upper) slider pin. After closer inspection, i see the brake pads biting against the rotor (just like braking).

How do i free the brake pads from the rotor so i can swing the caliper open? Is this normal?

Before i started, i tuned off power from the battery so the ABS doesn't do anything funny.

I can put key in the ignition and turn the steering around, but still the brake pads seemed to be biting the rotor.