Is it permissible to shorten the four-rak'ah prayers (Dhuhr and Asr) when working in an area 120 km away, knowing that one arrives home a little before Asr prayer or an hour after Asr prayer?

It is permissible to shorten and combine prayers for the aforementioned distance (the distance for shortening prayers), whether the traveler reaches his home before or after 'Asr. And whoever combines Dhuhr and 'Asr prayers by way of taqdeem (combining earlier) and then reaches his town, is not obligated to repeat them. The minimum distance for shortening prayers is approximately eighty-three kilometers, calculated from where the urban area of the town ends.