In Aguilar v. State, 621 S.W.2d 781, 783-84 (Tex. Crim. App. 1981), the Court of Criminal Appeals held that the 20-day period discussed in article 42.12, section 8(a)--the predecessor to section 21(b) containing substantively the same language--is triggered by the filing of the defendant's motion for the revocation hearing. The statute is silent as to the proper remedy once the 20-day period has passed without a hearing. However, until Aguilar in 1981, the appellate courts held that the proper remedy was reversal of the trial court's judgment and dismissal of the motion to revoke probation. See Ex parte Trillo, 540 S.W.2d 728 (Tex. Crim. App. 1976). In Aguilar, the Court of Criminal Appeals held: If the trial court fails to comply with the statute's requirements, the defendant may attack the legality of his confinement by means of the writ of habeas corpus. . . . However, the defendant may not await the revocation of his probation and then present a violation of the twenty-day requirement of Section 8(a) as a ground of error on appeal. Such a violation is not 'error' which taints the trial court's decision to revoke the probation and therefore mandates a reversal of the judgment. A violation of Section 8(a) merely amounts to unlawful prehearing confinement. Once the defendant's probation has been revoked he cannot be protected against such confinement. Thus we conclude that relief must be obtained, if at all, prior to the revocation of the defendant's probation. Aguilar, 621 S.W.2d at 786 .