Please help on how to change student visa

Hi, I wonder if anybody can help me on change visa from "fresh talent" into student?

I gained Master degree in Scotland and then applied "Fresh Talent: Working in Scotland Scheme" visa, which will be expired in Jan next year. I now have a offer from University for PhD course, and will then need to apply student visa. Somebody told me that for FT type visa, applicant can't extend for study purpose, and I'll have then go back to my country to apply a new student visa. Is that right? Do any of you know anything about it?

Please help!