I got continous B band for 3 years , am I eligible for c2 promotion ? And once promotion raised by manager how many months to take for promo

For giving promotion, there is no reason. But for denying promotion there are 100 reasons. So, be in the good books of your reporting manager and keep reminding him and he will get it done when promotion window opens.

Min 2 Bs needed in last 2 years. Once initiated then there is a different story.

3 years waiting for promotion is stupid

No… may be you need to wait 1 more

Bro how much hike you received when you get B band