The distance between the last house of the departure city and the first house of the destination city should be considered as the distance for prayer to be shortened.
The Paternal homeland of a person is not considered as the homeland of that person unless he/she stays there continuously for a long time like one year.
If a person wants to stay 10 days or more in a place, in this case prayers should be performed complete and the person must fast. And if this person wants to stay less than 10 days then prayers should be performed shortened and the person cannot fast. The beginning of 10 days is from the moment of entering the destination, for example from noon of the first day of arrival until noon of the next day is considered as one day.
This act is makrūh (abominable) unless this is the only way of having presence of the heart (full concentration).