The aircraft departs from the take-off airport, then enters the targeted airspace by means of the sector boundary fixes, and at last travels alongside the en route and continues to fly over a number of sector boundary fixes until it leaves the focused airspace. It is determined by take-off time, route length, and flight performance. Agreements have been sought with data providers to supply flight intentions for the present season and next season (as quickly as obtainable) along with common updates (daily, or weekly) of the initial info.