Except as provided in subsection (b), this subchapter and the amendments made by this subchapter shall be effective during the period beginning on December 18, 2015 and ending on September 30, 2025.

With respect to any action authorized by this subchapter or information obtained pursuant to an action authorized by this subchapter, which occurred before the date on which the provisions referred to in subsection (a) cease to have effect, the provisions of this subchapter shall continue in effect.