Is it permissible to shorten and combine prayers (either by delaying or advancing them) during work for an employee whose workplace is 150 km away from his city and 90 km away from his temporary residence, knowing that his employment contract is for 25 years?

The distance for qasr (shortening prayers) is approximately 83 kilometers, starting from the last inhabited buildings of the traveler's city to the first inhabited buildings of the destination city. Whoever covers this distance is permitted to avail themselves of the concessions of travel, such as shortening the four-unit prayers and combining the two prayers that share a time, unless they intend to stay for four days. Thus, if your workplace is 90 kilometers away from your residence and you do not intend to make a stay that would negate the ruling of travel, then it is permissible for you to combine Dhuhr with Asr and Maghrib with Isha, along with shortening the four-unit prayers, either by advancing or delaying them.