¶1Petitioner seeks review of his presumptive parole release date by this petition for writ of habeas corpus. We treat the petition for writ of habeas corpus as a petition for mandamus directed against the Commission. Moore v. Florida Parole and Probation Commission, 289 So.2d 719 (Fla. 1974), cert. denied, 417 U.S. 935, 94 S.Ct. 2649, 41 L.Ed.2d 239 (1974); Pannier v. Wainwright, 423 So.2d 533 (Fla. 5th DCA 1982); Fla.R.App.P. 9.040(c). We grant the writ of mandamus. The petition alleges that the Commission used an expired sentence in aggregation of petitioner’s PPRD, which is improper. Jordan v. Florida Parole and Probation Commission, 423 So.2d 450 (Fla. 1st DCA 1982). The Commission has failed to file a response to this Court’s order to show cause why relief should not be granted. Therefore, we accept petitioner’s allegation of improper aggregation and order the Commission to recompute his PPRD.
¶2WRIT GRANTED.