S.W.
I have followed an (EASY type) schedule with my kids too. The thought process of putting them down earlier so they sleep longer never worked for me. I know you say he's tired when you put him down but maybe extend his awake time a little... like just by 15 minutes or so.
The other thing... do you swaddle him? He may be waking himself up accidentally. At around six weeks a lot changes for them so really it could be a lot of things. But it may not get better very quick especially since we'll be changing the clocks this weekend.