Pemba, if your DHbis able to book, please come back and let us know as that will indicate they are letting younger people book, even if the front page doesn't say so.
It seems quite hit and miss with Group 6 being able to access the national booking site and some will be finding they are now eligible based on age criteria not CV. But it also sounds like some younger CV people are getting through when they weren't before, which is good.
Most of the younger CV have conditions which won't prevent them travelling to a bigger centres a bit further away, so they should do so if they can and not wait for more local. It is this which will mean they personally are vaccinated as soon as poss, but alsonthatbtheboist keeps moving and other people can be jabbed sooner too.