Hello everyone. I also had the same query regarding submission of IELTS score and had sent an email to the admission office. This is the response that I have received from the faculty:
Please send your language test results document to the Faculty of Law as an email attachment and we will upload it for you as you cannot upload documents after you have submitted your application. Please send your document to us using the following address:
llm@law.cam.ac.uk
Thanks
Did you send your email to them before 15 November or after?
I sent the mail to the Faculty of Law on November 29th.
Then, it is indeed possible to submit the scores after the application deadline.