Here are the final dates for 2012.
Round 1 & 2 - 5th & 6th May 2012 hosted by Cramlington & District MC
Round 3 & 4 - 26th & 27th August 2012 hosted by Witney MC
Round 5 & 6 - 6th & 7th October 2012 hosted by Greenbelt MC & Wickford AC
The regulations are out and can be got here MSA British Autocross Championship Regulations 2012