The World Federation One Stop Fiqh

Ruling 1336

With regard to a traveller who has made the intention to stay somewhere for ten days, if after performing a four rakʿah prayer within its prescribed time he wants to go somewhere else that is less than eight farsakhs away, then in the event that he is unsure whether or not he will return to his first destination, or he is totally unmindful about returning there, or he wants to return but is unsure whether or not he will stay there for ten days, or he is unmindful about staying there for ten days or travelling from there, then in these cases, he must perform tamām prayers from the time he goes until the time he returns and after he returns as well.