Our Shaykh, Muḥammad ibn Ḥizām, may Allāh preserve him, was asked the following question:
Question: “A man travelled to a land to stay a day or two, or a little longer, does he shorten and combine his prayers until he returns to his country?
Answer: “As long as the man has determined that he will stay a day, two, three or four days, he continues to shorten until he travels because this time period does not take him out of being considered a traveller. That which indicates to that is what is comes in the Ṣaḥīḥain from the narration of Ibn ‘Abbās that the Prophet ﷺ reached Makkah the morning of the fourth of Dhul-Ḥijja and he remained there in Makkah shortening his prayers until the eighth day (of Dhul-Ḥijja) ,a total of four days. Also, the Prophet ﷺ was determined to remain there for four days until he left to Minā, so during this time he ﷺ continued shortening [his prayers]. But if he is determined to stay longer than four days, he takes the ruling of a resident as soon as he reaches, so he completes his prayers. This is if he is determined to stay more than four days and is not doubtful. If he is doubtful and he doesn’t know how long he will stay, a day, two, three, four or longer than that, then he continues to shorten because he is not determined to stay continuously in a specific place. Similarly, the one who moves around from place to place due to some work. He comes to here for example, then after a few days he goes to Ba’dān (a town in the province of Ibb, Yemen), then after that he goes to Ḥubaysh (another town in the province of Ibb, Yemen), it is not said of him that he is a resident in Ibb because these places are distant to one another. [Another] example is if he is determined to stay in Ibb two or three days. He will go to Ḥubaysh a day or two and then to Ba’dān, even if he is determined to travel ten days altogether yet he continues to move from place to place, i.e. he doesn’t remain in one place during that period, then he is still considered a traveller.” End. [Reference]
Majid Jawed Al-Afghanee