Have a look here :-
Recommended Retention Size Limits (RRSLs) & DEFRA Minimum Landing Sizes (MLSs)
According to this 36 cm around here as of April 2011 each authority has its own rules so just click on you region.
Areet Ian,I don't find it confusing its good that angling clubs set higher limit sizes for bass and other species.
Good on the clubs.
off topic, I only wish they would try and improve and reduce littering during the competitions.