An admissions officer at one of the grammars (not one in which I have an interest so it wasn't said to make a point) told me that she only finds out the night before which children have been successful in gaining places. She had got a bit fed up of parents ringing up a couple of weeks ago hoping to get some inside information which she genuinely didn't have. So no leaks are likely to come from the school.
Then come 1st March, she'll be inundated with parents asking where they are on the waiting list and/or how to appeal. If you can, try & leave it a few days before calling.
Details on how to appeal should be in with the LEA letter (or maybe from the school). If you do need to appeal, there's no need to panic or rush - there's no priority given to those getting the appeal form in first!
Hopefully, though (fingers crossed) everyone here will not have to appeal.