Usually the opening times for the NS are announced end of Jan/Feb
As Guy says, Ben Lovejoys site tells you more than you'll ever need to know about it.
I've been over 3 times and there's nothing else quite like it [ thumbs up ]
Yes it is daunting and oh boy is it slippery in the wet
I locked up going into Aremberg in the wet last year, 1st lap of the trip as well !
Some pics and info on my site
www.gvk-motorsport.co.uk