The Ulama in Canada are divided on the starting time of Fajr and the ending time of Sehri.

Answer

As long as the Fajr time is not physically determined by observation of the natural phenomena, the big difference among the Ulama will remain. There is an imperative need for the Ulama to form a committee who will determine the Fajr time by physical observation of the Khait-e-Aswad and Khait-e-Abyadh'. Such a committee will have to be in existence for just one year. Thereafter they will have a valid and an absolutely correct perpetual timetable for Fajr and Sehri.

Currently, different groups are relying on different timetables prepared from astronomical calculations, hence the sharp difference in the times of the different groups. If they are not prepared to form a committee for just one year and make the little 'sacrifice', then obviously the conflict will be perpetual.

As far as Isha' time is concerned, it is extremely simple to solve the difference. Regarding Fajr, there are some inconveniences and difficulties.

But, establishing the correct Isha; time is quite simple. They just have to observe the disappearance of the whitish glow (Shafaq-e-Abyadh) in the western horizon for determining the correct Isha' time, and if they are Shaafi's or Hambalis, then it will be the disappearance of Shafaq-e-Ahmar. For Fajr, they will have to go to the sea or to some appropriate place to observe the natural phenomena. But the Isha' time could be determined from nearby where tall building are not blocking the horizon.