Sanjan, not Surat. This story is unsubstantiated nonsense, and there is little to no evidence that the Parsis were originally refugees. Archaeological expeditions were already done in Sanjan, you can look up the results.
> That the Zoroastrian migrants to Sanjan were basically a mercantile group is borne out by records as well as by excavated material. Andre Wink goes further and adds that the migration was not so much due to religious persecution as much as ‘a readjustment of commercial patterns which had arisen long before Islam, and, to an extent at least, a response to new opportunities in the transit trade between the Islamic world and al-Hind’
THE LANDING OF THE ZOROASTRIANS AT SANJAN
The archaeological evidence - Rukshana Nanji and Homi Dhalla
> That the Zoroastrian migrants to Sanjan were basically a mercantile group is borne out by records as well as by excavated material. Andre Wink goes further and adds that the migration was not so much due to religious persecution as much as ‘a readjustment of commercial patterns which had arisen long before Islam, and, to an extent at least, a response to new opportunities in the transit trade between the Islamic world and al-Hind’
THE LANDING OF THE ZOROASTRIANS AT SANJAN The archaeological evidence - Rukshana Nanji and Homi Dhalla