The Brentwood wood pigeon club still exists.
They don’t have a website but can be contacted via email email@example.com
Joining the club is very lengthy and can take up to four months.
Due to Corvid virus, interviews are taking a long time. The criteria is, you must be experienced in pigeon shooting. You will be questioned on health and safety and good shooting practices and undertake trial shooting, irrespective of your shooting abilities.
It is preferable you are sponsored by an existing member.
Hope this helps