DiCicco is now Principal Deputy Assistant Attorney General

John DiCicco's time to serve as Assistant Attorney General ran out, so he was given a new, specially created title, in the absence of an Assistant Attorney General so that he could continue to run the Tax Divisoin.  That title is Principal Deputy Assistant Attorney General.  Main Justice has an article giving some of the details titled Manuever Allows Career Lawyer to Wield Power in Tax Division.  (Note that you may have to create an account with Main Justice to read the article, but those interested in the Tax Division and DOJ generally will want to do that.)  The article cites Tax Division Directive No. 139 as to authorities delegated during the period of the absence of an AAG.  Finally, the article notes the Administration claim that the appointment of an AAG is in the works.