What is the preferable method for combining prayers during travel: combining them in the time of the first prayer, or in the time of the second prayer?

Primary text

The preferable method for combining prayers during travel is a matter of scholarly difference. One position states that combining them in the time of the first prayer is superior because it offers greater ease and concession, similar to shortening the prayer (Qasr). Another view holds that combining them in the time of the second prayer is preferable because it avoids differing scholarly opinions and because the Prophet, peace be upon him, did not consistently practice combining them in the time of the first prayer, which suggests it was not superior, unlike the practice of shortening the prayer which was consistently maintained.