Trending @Cognizant; Can someone tell me the actual time-line of promotions in CTS?

We were rebadged from a different organization last year and the lack of proper information from. CTS is shocking. What is the cycle for promotions? Is it that the process begins after 18 months and then you get it on papers after 24 months from DOJ? Or is it that if you are a 5 rating you can get promoted within a year ?