It was probably only a matter of time before an independent trade event was born. BBKA did a great job over the years in bolting on a trade event to a lecture convention, and may continue to do so. But business is business, and any commercial organisation will do what they need to do for the good of their business, and the Spring convention does not lend itself to big enough sales for various reasons, including the geography. You'll find most traders will attend both events - combined footfall over 2 events probably significantly higher than if a single event had been held. I'll probably go to both given I live equidistant between them, but an additional event will attract extra custom on the whole