In June 2023 the UK Government announced that it intended to make some changes to the UK immigration system on 1st January 2024.
These changes include:
"Removing the right for international students to bring dependants unless they are on postgraduate courses currently designated as research programmes.”
"Removing the ability for international students to switch out of the student route into work routes before their studies have been completed.”
"Reviewing the maintenance requirements for students and dependants.”
On 17th July 2023, the government released it's formal Statement of Changes to the Immigration Law, which added further clarification to some of the intentions above.
This Statement confirms that international students, who start their course after 1st January 2024, will not be eligible to apply for dependants to join them in the UK. The only exceptions to this will be those who are government sponsored (on course of more than 6 months) or those studying PG Research courses (PhD).
Conversely, those whose courses start before 1st Jan 2024 (so September/Autumn 2023) will still be able to apply to bring their dependants to the UK. They do not have to make their dependant applications at the same time as their own visa application but can make this application at any point during the duration of their course.
Regarding switching from Student to Work routes in the UK, clarification has been made that students will not be able to switch into a work route until they have completed their course. The only exception to this is for PhD students who have already completed 24 months of their course at the time of switching or students who had already made a visa application to switch before 17th JUly 2023.
You may also find the UK Council for International Student Affairs (UKCISA) a useful resource, so please also check there.