Just to answer a few questions I see posted ...
How long will it take for the IRS letter to come ?
Expect it to take as long as 2 weeks and be happy if it comes in sooner.
Why am I being "reviewed/audited" ?
What the IRS looks for each year is a closely guarded secret and they change from year to year so even if your return is exactly the same as prior years you could be stopped for a review of some kind. And some returns are pulled totally at random. There is nothing you can do but wait patiently while the IRS processes your return. If you do get an IRS letter read it carefully and respond as directed in a timely manner.
Why did someone else's return process faster than mine when we filed at the same time?
As I have posted in the past ... think of the IRS processing machine as a long "pipeline" with "filters" in it ... some returns will slide straight thru with no stops. Some returns will be filtered out for some kind of review (computer or human) then put back in the pipeline where it may not get stopped again or it can get stopped several times. Each stop along the way can add more time to the journey and if the review requires a human interaction the time line just got longer.
As for all the PATH returns ... they were stopped by a filter at the beginning of the pipeline and put in a "holding pool". Once the 15th came they pushed those millions of returns back in the pipeline for continued processing where some will now slide straight thru and some will be stopped by one or more filters. They were not at the end of the process awaiting the 15th to release the DDD which is why it took a week to start getting DD Dates.
