Well, took me a while since i played ALOT of alt chars.
CR0-4 took about 3 months from leading squads every once in a while.
CR4-5 took 2 months from leading a squad 3+ hours every day. I could've done it in 3 weeks if i lead squads all day and only played that char
Currently working on CR5 on my VS/werner char, cr2.5 atm from leading a squad a few hrs a day.