Metrolinx is leading the project to develop the Queen St Hwy 7 Bus Rapid Transit, Preliminary Design Business Case (PDBC) in accordance with the Transit Project Assessment Process (TPAP, under O.Reg. 231/08), Metrolinx is developing the Queen St Hwy 7 Bus Rapid Transit, Preliminary Design Business Case (PDBC) in accordance with the Transit Project Assessment Process (TPAP), under O.Reg. 231/08).