Correct. 61.58 to include instrument proficiency. Also a full ATP check ride.
How long it takes depends on many factors. If you applied to the vacancy announcement on USA Jobs it depends on where you are available to work. For offices who have vacancies it might not take long. The agency tries to hold to the 80 day hiring model, from vacancy to entry on duty. But sometimes security, drug test, etc... take longer.
You won't get a letter saying you weren't hired.