
    Marvin LANCASTER, Appellant, v. FLORIDA DEPARTMENT OF CORRECTIONS, Appellee.
    No. 1D14-5683.
    District Court of Appeal of Florida, First District.
    Dec. 1, 2015.
    Marvin Lancaster, pro se, Appellant.
    Lisa Martin, Assistant General Counsel, Florida Department of Corrections, Tallahassee, for Appellee.
   PER CURIAM.

Appellant challenges the circuit court’s order which dismissed his petition for writ of mandamus as res judicata, on grounds that the previous order relied upon by the circuit court also ruled the matter res judi-cata and thus was not a ruling on the merits. See Miller v. Fla. Dep’t of Corrs., 153 So.3d 392 (Fla. 1st DCA 2014).

Appellant correctly asserts that the order dismissing the action in Lancaster v. Florida Department of Corrections, No. 2013 CA 001016 (Fla. 6th Cir.Ct. May 21, 2013), was not on the merits, but rather dismissed that action as res judicata. However, the orders relied upon by the Sixth Judicial Circuit in that case were rulings on the merits of-Appellant’s sentence structure and calculation claim. He reiterated the same claim in case number 2013 CA 001016 in the Sixth Circuit, and in the circuit court case underlying this appeal, Lancaster v. Fla. Department of Corrections, No. 2014 CA 001529 (Fla.2d Cir. Ct. Oct. 14, 2014). As discussed in the Sixth Circuit’s order, the merits of Appellant’s claim were denied by the Second Judicial Circuit in Leon County by final order in Lancaster v. McNeil, No. 2007 CA 002150 (Fla.2d Cir.Ct. Oct. 16, 2008), certiorari denied, Lancaster v. McNeil, 10 So.3d 635 (Fla. 1st DCA 2009); In addition, and also discussed in the Sixth Circuit Court’s order, Appellant’s challenge to the Department of Corrections’ structure of his sentence based in part on gain time awards was denied on the merits.by the» District Court of the Northern District of Florida in Lancaster v. Tucker, No. 3:09-cv-333/MCR/MD, 2012 WL 399206 (N.D.Fla. Feb. 8, 2012).

The circuit court correctly found that Appellant’s challenge to the Florida Department of Corrections’ calculation of his tentative release date, including the correct application of gain time, was res judi-cata. Accordingly, the order dismissing the action is AFFIRMED.

WOLF, BILBREY, and WINOKUR, JJ., concur. 
      
      . It also appears that Appellant’s challenge to the Department’s calculation of his tentative release date as described in a Department memorandum dated March 25, 2009, is moot, due to the Department’s update of Appellant's tentative release date since that time.
     