What happens if a traveler forms the intention to reside (Iqama) during the first prayer when combining prayers due to travel?

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If a traveler intends to reside while performing the first prayer of a combined set, the permission for combination and shortening (Qasr) is immediately nullified, and the traveler must complete the prayer in full (Itmam). If the traveler subsequently forms the intention to travel again, making use of concession is not permitted until they have left the town where they resided.