The website has now been updated with the following regulations:
Wessex Championship: https://www.claypigeonkartclub.com/wessex-challenge/
Rotax Festival: https://www.claypigeonkartclub.com/rotax-festival/
Also, there was a mix up with the website which left old versions of the Championship and Supplementary regulations up. This has now been corrected. The correct page hosting these is https://www.claypigeonkartclub.com/regulations/ and the regulations have been updated for the 2021 season. The other pages have now been removed.