I'm not sure how come but I think the rules are different in Wales. I looked into it some years (maybe 6 years) ago, so there could have been changes since.
Anyway, at that time, in Wales the household could eat the meat, and it was legal to have someone come and slaughter on the holding for you. In England, as people have been saying, the official line was that only the slaughterer could eat the meat, not other family members, and the slaughterer had to live on the holding.
I would much prefer it done at home, it has to be less stressful for the pigs, doesn't it?
It was inevitable that this topic would go off into a general discussion on home-killing - sorry, Karen!