I am using 2013 study text from one of the tuition providers. Am I okay to use the same considering the fact that the paper format has changed from next exam session?
It is OK to use the 2013 text because the syllabus itself has not changed and therefore your studying is not affected.
However it would be a good idea to get a new Revision/Exam Kit. Practicing questions is the most important thing of all, and the new Revision/Exam Kits have lots of exam-standard questions of the same type as will be in the exam.