I do not know your tractor but one issue arising on some models is the confusion the warm block causes for the automation of the GP timer.
The timer sees the warm block and deduces there is no need for GP's. As the engine cranks and inhales very cold air, it does not want to fire.
On common rail fuel injection engines, the dealer can change the sensor used to decide GP time from the engine block sensor to the mass air flow sensor.
Now the GP warm time will be appropriate for the outdoor air temp.
On my 2012 pre common rail engine, the block heater was causing starting problems as described above. I was shown a dealer trick which gives me manual control of the GP warm time. Shuttle shift in forward and turn key to start.
You have on indication on the dash but the GP's are heating. Count to 10, shuttle back to neutral and crank engine. It fires instantly.
Dave