Can I switch into other employment categories? (from www.workingintheuk.gov.uk)
Fresh Talent: Working in Scotland scheme participants will be eligible to switch in-country into leave as a:
work permit holder, if the work permit is for employment in Scotland
Highly Skilled Migrant Programme (HSMP) participant
Business person
Innovator
You would have to show that you meet the requirements of the category you apply to switch into. Further information on these schemes is available on this website.
If you do not switch into one of these categories, you will have to leave the UK by the time your leave expires.