You will have to re-apply to TSA for the new training event. Your company have to give you the training ID code and some other info. once you submit those TSA will send you an e-mail saying that your request has been approved and will give you guide you to a web site for finger prints.Now since its 121 company and it's initial training/type you will have to re do the finger prints only once. I think it's about 70 USD. Once your fingerprints clear you can start flight training (simulators). You DON'T have to have clearence for groundschool.Also when you go for recurrent training company will get you the clearance, BUT if you go for upgrade you have to re apply for upgrade training but not fingerprints assuming fingerprints were done with 15 months.
My friend make sure you get all the info from your company in order to request training before the class starts. Good luck and you can pm me if you have any questions.