There are 3 roads here. Middle Road, Lower Middle Road and Upper Middle Road.
In mississauga, there is one concession road between Lakeshore and Dundas, and that is Middle Road.
You will notice at the Mississauga - Oakville boundary, the lake dips south. Through most of Oakville, there are 2 concession roads between Lakeshore and Dundas, these were Lower and Upper Middle Road. At the Ford plant, the QEW dips a bit and switches from Middle Road to Lower Middle Road.
I need to check an old map on exactly what the current Royal Windsor Dr. was called between Southdown to Winston Churchill to comple the picture.