We put their names down just over a year before DD1 was due to start and 2 years for DD2. It would have been sooner, but we only just moved to the area (far away from where we used to be). DD1 only just got in because of a last minute cancellation.

Definitely ask for a tour of the school, and ask them what programmes they have as well as other stuff such as sports, music and art programmes, community based programmes, bullying policy etc. You're interviewing them as much as they are you.