He was released by Glasgow Warriors at the end of the 2020-21 season and was quickly signed by the Ayrshire Bulls for the 2021-22 season.[9]
International career
Thornton represented Scotland under 18s five times scoring one try.[5] He made his debut for Scotland under 20s in the Six Nations match against England. He played in the 2017 Under 20 Six Nations Championship and the Under 20 World Rugby Championship.[5] He started in all of Scotland's 5 matches in Georgia.[2] Thornton is Scottish qualified through his mother from North Berwick.[2]