Re: hard brake pedal
Welcome to the garage.
I would just drain some fluid at each caliper and see how it looks like, but since the brake works ok after some time, i wonder if the problem is not with the pistons and or seals. Looks like that the pistons are stuck and only the rear brakes work in the beginning. After sitting for a while (long enough for the problem to be there), let a helper push the brake pedal and look if you can see the front brakes being applied.