The exact same thing happened to me. I was on the Full House bundle and renewed and they told me everything was to remain the same... however they put me on the 'MAXIT' bundle which removes the kids channels in favour of a £5 a month subscription.
I have just called the cancellations department (customer services can't fix this). They added those back on and credited me with £5 a month. Just watch though, this will probably not be the case next time you 'renew'.