Is it permissible for a traveler to shorten and combine prayers until he is certain of his permanent settlement in a country, or does the obligation of his return to his homeland prevent that?

A traveler's concessions for travel cease if he intends to reside in a place for four days or more. He is no longer considered a traveler, and he is obligated to pray in full. He is not permitted to combine prayers unless there are valid excuses that allow a resident to combine them.