Is it permissible to combine and shorten the Dhuhr and Asr prayers before their due times because of work?

If the preacher (Imam) intended by "shortening" not to prolong the recitation and the pillars of the prayer, without compromising its fundamental elements, then the prayer is valid.

However, if he intended to shorten the four-rak'ah prayer to two rak'ahs for a resident due to work, this is incorrect and contrary to the consensus of scholars. Shortening (Qasr) is a concession for travel and is not permissible for a resident.

Regarding combining prayers (Jam‘) for a resident: it is not permissible except when there is a hardship and difficulty that prevents performing each prayer at its appointed time, and this must be due to an incidental reason, not a regular habit, based on the hadith of Ibn Abbas about the Prophet (peace be upon him) combining prayers in Medina without fear or rain. It is not permissible to combine all prayers at one time under the pretext of work, neither for a resident nor for a traveler.