Masons Lane has been closed at the Evergreen Mill Rd. The entrance is simply no longer there. When your GPS brings you in on this side, the new section of Battlefield Parkway is what you will find instead. Follow the big orange Masons Lane Detour signs. They will lead you to the new light at Rt15 and Masons Lane by leading you down Battlefield Parkway and making you turn left onto Rt 15 heading south away from Leesburg and then another left onto Masons Lane and the light.
Here is where it gets weird: Just after you turn onto Masons Lane there will be big "ROAD CLOSED" closed signs blocking the road. You have to drive around them.
In this picture, Al's Orchid Greenhouse is two driveways beyond the road closed sign. 204 Masons lane. You are local traffic if you are coming here. You are allowed to go around. :-)