NOT BRITISH SWIMMING
I think initially it's very important at this point that I draw the distinction between the ASA and British Swimming because they are two quite separate and distinct organisations, with different functions.
British swimming is a Federation of the 3 home countries England Scotland and Wales, and it deals with the performance end of swimming
Wikipaedia says the ASA was the first sport governing body of swimming to be established in the world and today remains the English national governing body for swimming, diving, water polo, open water swimming, and synchronised swimming.
The ASA deals with everything below that at an English level, i.e. clubs membership, et cetera I may be teaching my grandmother to suck eggs but there is a general tendency to confuse and conflate the two.