This web reference shows the meaning of every IRS transaction code: https://www.auditdetective.com/Transaction_Code_Definitions.html
According to this website, 424 means your return is going to be examined to see if an actual audit should begin: https://www.astps.org/wp-content/uploads/Detect-an-Audit-Slides.pdf
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
