Before allowing you to transfer to any other course or level of study, other than that stated on your CAS, the University is required to justify to UKVI that this represents academic progression.
UKVI want to see that you are making progress on your degree by progressing through the stages, and that each course you undertake is higher up on the RQF (Regulated Qualifications Framework) scale than your previous study in the UK.
Generally, any transfer that means you drop down a stage or an academic level would not be permitted as it does not represent academic progression. For example if you were currently studying in stage 3 and wanted to transfer to another course and start at stage 1.
In order to justify if a course transfer meets UKVI academic progression requirements, we would look at two main things; are you continuing your studies in the same subject area, or does the course transfer support your genuine career aspirations. Therefore, it is important to provide evidence to support why you wish to transfer, and we may ask you to write a detailed personal statement for this reason.
In some cases, we may not be able to support your request to change course, if we as your Student visa sponsor feel that it does not represent academic progression. You should be aware of these requirements and ensure that when making your initial application you have carefully researched your chosen course.