What is the ruling regarding the 'Ishā prayer for someone residing in a country where the white twilight (al-shafaq al-abyaḍ) or sometimes the red twilight (al-shafaq al-aḥmar) does not disappear, and when should he pray?

The time for the 'Isha prayer begins with the disappearance of the red twilight according to the majority of scholars. Whoever resides in a country where the night is very short is obligated to pray 'Isha like everyone else, but it is forbidden for him to perform it before its time or to delay it past its time, making it a missed (qada') prayer. If the twilight does not disappear until dawn, or if it disappears at a time insufficient for performing the 'Isha prayer before dawn, then the people of that country should estimate the 'Isha prayer time by looking at the closest country to them that has a discernible 'Isha time. And it is also said: they should act according to the timetable of Makkah al-Mukarramah.