(a) A judge granting community supervision to a defendant convicted of an offense punishable under § 550.021(c)(1)(A), Transportation Code, shall require as a condition of community supervision that the defendant submit to a term of confinement of not less than 120 days.
(b) If a sentence of confinement is imposed on the revocation of community supervision, the term of confinement served under Subsection (a) may not be credited toward completion of the sentence imposed.