This will affect students who are on a course which has an optional placement year or year abroad.
Students who progress to the final year are registered on stage 4 so those students who have opted to take the placement year or year abroad can be registered on stage 3. If you are not taking the optional placement year or year abroad, it is correct for you to register on stage 4 in your final year.
If you had a period of interruption (which may be the case for postgraduate research students), the system will record the number of academic years since commencement. Your actual deadline will have been adjusted for both the purpose of the end date of your programme and the level of fees you will be liable for.