2 U.S. Code § 1881d
2 U.S. Code § 1881d is about Effective date. It is under Subchapter V (Capitol-flown Flags for Families of Fallen Heroes) of Chapter 28 (Architect of the Capitol) of Title 2 (The Congress) of the Code.
This subchapter shall take effect on May 16, 2016, except that a Capitol-flown flag may not be provided under section 1881a of this title until the regulations issued under section 1881b(a) of this title take effect in accordance with section 1881b(b) of this title.