Its’ pretty much a give now, that If you change your FP in your GPS, and then ask for another clearance, then ATC know, and give you a new clearance to match your current GPS flight plan.
ie MSFS ATC has a tracker virus installed in your GPS 
Its’ pretty much a give now, that If you change your FP in your GPS, and then ask for another clearance, then ATC know, and give you a new clearance to match your current GPS flight plan.
ie MSFS ATC has a tracker virus installed in your GPS