Doing maths GCSE a year early

[Marmitelover55]

DD2 is in year 7 and we've just had parents evening. She is in the top set and her maths teacher told me that they will complete the year 7/8 syllabus this year and then start the GCSE syllabus in year 8. They will study this for 3 years and sit the GCSE at the end of year 10. In year 11 they will then study additional maths/further maths (sorry can't remember which) and sit that exam at the end if year 11. I understood that it's not advisable to sit GCSEs early so should I be worried about this? She is at a good comp if that makes any difference.

It is probably less of a challenge for high ability DCs to focus on the maths GCSE and perhaps another couple of GCSEs and get a top grade a year earlier than to take all their GCSEs at once in year 11 so I am not convinced that extra credit is due.
Precisely