Is it permissible to combine and shorten prayers (Dhuhr two rak'ahs, Asr two rak'ahs, Maghrib three rak'ahs, Isha two rak'ahs) when arriving late after the Isha prayer for a traveler who will spend 14 days at a job located more than 800 kilometers away, and who only shortens prayers on the days of departure and return?

It is permissible to avail oneself of the concessions of travel for distances that reach the minimum distance for shortening prayers (qasr) between your city and your workplace. These concessions include shortening the four-rak'ah prayers (Dhuhr, Asr, and Isha) and combining prayers. As for Fajr and Maghrib, they are not shortened. If you arrive at your workplace and intend to stay there for more than four days, you are considered a resident, and it is not permissible for you to shorten or combine prayers. You must perform each prayer fully at its prescribed time until you begin a new journey. It is not permissible to delay a prayer beyond its time under the pretext of travel; rather, it must be performed within its time, with the possibility of shortening and combining.