ATAS for extending Visa

Hi Everyone,
I am a PhD student and have to apply for Visa extension by the end of the month Jan30 2014. I hd applied for ATAS on Nov 25th 2013 and not yet received the clearance certificate. My question is can I apply for visa stating that I am waiting for the ATAS? I got ATAS let time during the start of the course and this is for extending Visa. Do the they consider this and wait till I submit the ATAS?
Please let me know if you have any suggestions or answers as I am really worried.

Thanks

You need your ATAS certificate without it University will not be able to issue your CAS. Please contact ATAS to find out why it is taking long? Also contact your University so they can assist you further

Thank you for the reply. I have received CAS from the university. So if I submit CAS with my Visa application do you think they can wait until I receive ATAS. I am already a student and studied for three years. I am extending for writing the Thesis.
And yes I have contacted ATAS by email but haven't received any reply.

Thanks,

Assuming you are applying from within the UK, yes you can apply providing evidence that you have made your application and they will usually hold the decision until you send them your ATAS certificate. Would advise you to use Tier 4 Print and Send form rather than TIer 4 student Online form as easier to explain re. missing docs with print and send.

Thanks a lot all your responses are really helpful and much appreciated. Will keep updating the status.

Hello everyone. Finally I have received my ATAS!! Thanks a lot for the suggestions.