Tier 4 visa extensions: Apply early
(15 June 2012)
If you need to extend your Student Visa to complete your current course, you can apply as soon as you have your CAS and other requirements for your application.
It is advisable to start preparing your application at least 12 weeks before your current visa expires so that you give yourself enough time.
Where possible, you should request your CAS at least 12 weeks before your current visa expires.