For the OP, you need to go to a different dealer. The Grid heaters must cycle or you will have a no start issue when it gets colder, not to mention very rough hard starts for the engine and emissions system. When you start the truck while you are out and in it, are you keeping the door open? I quite often just push the brake with my hand and press the start button and watch the timer count down but have to press the start button again to get the starter to kick in. This is only with the door open. Not really related, but these trucks do odd things if you do something out of the "normal".
Hopefully when they call in they would likely get a different tech that isn't sitting in Key West Florida or something and has no idea of what a grid heater would be for and have a little more common sense!
As for the app for the remote start, Yea, us Canadians get the shaft on this one. When I ordered my truck I was looking forward to setting this thing up as I had seen it on tv commercials, but then too found out that you can only get the app on the American iTunes store and not the Canadian one. I felt like the victim of false advertisements!