Remember that thread about only a tiny handful of pupils getting all 9s?
According to one local newspaper (unfortunately they don't give a reference):
There were only 732 pupils across England who scored a clean sweep of top 9 grades in all their GCSE
www.bucksfreepress.co.uk/news/16594185.gsce-results-day-2018-get-the-latest-live-updates-from-schools-across-bucks/
Brighton College say five of their pupils gained 10 Grade 9s so the overall figure sounds roughly correct.
www.theguardian.com/education/2018/aug/23/gcses-boys-close-gap-on-girls-after-exams-overhaul