I only use ilac and I haven't had any problems with them at all, but I do strictly follow their instructions, I normally get min 2-3 weeks chip free, it usually grows out first, so I have to change it.
I'm not sure to be honest, and you have to be friends with someone already in the group to be added. As its a closed group I didn't think there was a group at all as it doesn't come up in searches so I started my own group for everyone to ask questions, swap colours etc but there's not many members! haha then I realised there was a closed group, must be where all the ink London people are! XI've also been waiting several weeks. Is it run by any of the ink London team? Does anyone know?