Whether you are a member or not you can use the events filter on British cycling website
This will give you all so you can choose
I can’t remember guisburn blues but based on guisburn red the blues would be way more technical than anything classed as kids XC which tend more towards a CX course in our experience
Rider Ability differs massively between different places. We are down souf but local type races where we live seem to involve kids who don’t do much actual riding (lots of classroom stuff and riding round cones) whereas some of the events we have to travel for competition is stiff from local clubs.
We aren’t part of a club so we get excluded from some members only races but the loss of real riding time to actually join a club is not worth being allowed to enter some extra races so we only “do opens” but your local club might be one of the “good ones”
We also found the “good clubs” with competent riders rather than some classroom approach are much more social. Kids racing each other one minute then going off riding together with and without parents and making friends.
The same clubs also seem to be open races anyway so you aren’t missing out if you don’t join (for us there are great clubs 1-2 hours drive away but I can’t do that every week)