The Lailathul Qadr will be any odd days of last 10 days of Ramadan. As I studied, in this sacred day, Jibreel and other angels will come to the Earth at the time of Magreb and will return at the time of Subhi. As we know, the time is different according to place to place. Then how do they come to one time to the Earth at the time of Magreb. Or it means they will launch to Earth at the time of Magreb at Makkah? Please clarify

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

Laylat Al Qadr falls in every part of the world according to its position in the Hemisphere. This night can be shared by many countries at the same time. Other countries might share part of it with some regions and part of it with other regions according to the position of the earth from the Sun. So, the night of Al Qadr comes for each people in the time they usually call night (i.e. from sunset to dawn). It can start in a region before another one and similarly it can end in some regions while still on in others. Angels know the time of their comings and goings better than we do here. They are always on schedule.
Allah knows best.