Headteachers cannot alter their original order of suitability - their rankings are published by BCC as an appendix in the appeal papers.
What they might
be able to do is indicate that things have changed. For example, they could write a comment "There has been a marked improvement in Mary's work recently and we would now rank her as 5th rather than 10th".
Similarly, although the original recommendation remains on the record, they could
revise it (e.g. from a "2" to a "1"). In fact, I seem to recall there used to be a space on the headteacher's statement where they could indicate any change.
The longer the gap between the original recommendation and any update, the better!
If headteachers submitted their recommendations on 17th November (the deadline), then I doubt whether they would be in a position to change anything on 1st December!
If parents think their child is on an upward curve, then rather than pressurising headteachers now, I would suggest just before the appeal checking with the head whether he/she could confirm any change and would write a last-minute letter to the appeal panel with an update.
Spare a thought for headteachers (well, just a little one
) who will be under a lot of pressure from anxious parents at the moment.