Trending @Accenture; How many years it will take to get promoted from level 10 to 9?

It depends upon who you are, usually promotion goes as per below :-

In Accenture, promotions are done as per below prioritised list. Some time pt 1 and 2 can be replaced

1. Iif you are your manager’s favourite
2. If you are a female
3. If you are from special category
4. If you are male and not covering any of above.

There can be more scenarios added before pt 4

Atleast 24 months