Yes, I was aware the cut off point was 336 as the minimum mark for 2012 but could not answer the actual cut off to get in as per the last boy as you probably have to contact the school or parents of the particular DS for this. This is why I did not say ZZZ equals 336 but was only giving a number to the cut off referred to by Reading Mum.
It would be nice to know the cut off score for the last child getting in but not necessarily that useful as the last child to accept may have entered partially through the academic term replacing a child who is leaving for other reasons. However this child could have been for example: number 329 on the waiting list but only because waiting list no.s 314 to 328 did not want the space as they had settled in their new school, moved, etc. So for the present situation, where parents want to know their chances prior to the March LA offer, it may be probably be best to ask what no. in the waiting list was the last child to be accepted before the start of term as the score may differ a bit between 314 to 329. Therefore the actual cut off score my be less useful in this case as long as they are above the minimum cut off.
BTW : Sorry for any confusion as to the clarity of which cut off I was giving (prior to your edit).
Nice graph though!