We are one of the 18 (must be a Royal 'We' - should say DS is one of the 18!)
He took the test for Marling, but partly due to mild reading problems, didn't get in. We were quite happy with this as, although bright, didn't think it would be the right school and were looking forward to getting a place at TK as we are in the catchment.
Then, as you say, we didn't get a place.
TK were quite surprised by this apparently and petitioned GCC to allow all those in the catchment to have a place. They were successful and all catchment children that wanted one have, I believe, now got a place there.
DS is already very happily settled, despite initially being rather upset about missing out on Marling.