IRS is a mess in my opinion.  My experience in past years, client would have received the letter about an adjustment before the refund was issued.  This year I had a client receive letter nearly two weeks after refund was direct deposited.   This client - like many others - believes I should know this adjustment happened and why it happened without ever seeing the letter.   I agree it is difficult to tell clients  "I don't know" but it is an honest answer.