When do you take out the head protector from baby car seat?

[Asturimama]

I was wondering whehter there are any guidelines on weight/lenght/age of the baby as to when to remove the head rest from the sit.

My ds is 8 weeks but on the long side and he looks a bit too snug with the head protector on (it is sown together with an extra back rest that goes down to his bum). I already removed the "bumper mattres" that was underneath but I am not sure if I should remove the rest as then his head will not be supported and he can´t fully hold it yet (he´s only 8 weeks)

(By the way, the car seat is a Bebecar Easybob=

I think it's around 12 weeks but I guess it depends a bit how big/strong your baby is. I don't know the car seat. Can you move the shoulder straps up at all so the head hugger gets lifted higher up?

There is another set of slits to pull the shoulder straps up, and this is what I intended to do, but on the instructions it says first remove the "bumper mattress", then the head protector and finally move the straps up, that is why I am a bit confused...

I have a different seat but my DD got too big for the newborn insert so I had to remove it. She needed extra head support so I got some of the comfort wrap things that go round the straps. Just cushions her head enough to be comfortable. She is nearly 7 weeks.