A method including monitoring a plurality of elevators, wherein at least two of the plurality of elevators are set into a shuttle mode in which the corresponding elevator travels between two pre-defined floors; calculating at least one of an arrival time and a departure time of an elevator car of each of the at least two elevators in the shuttle mode at a predetermined floor; determining a time required by a user for reaching each of the at least two elevators in the shuttle mode from an operation terminal location; calculating a preference order of the at least two elevators in the shuttle mode on the basis of the time of arrival and/or departure of the elevator car of each of the at least two elevators in the shuttle mode and the time required by the user for reaching each of the at least two elevators in the shuttle mode from the operation terminal location; assigning one of a plurality of display modes to each of the at least two elevators in the shuttle mode according to the preference order; and causing displaying of an elevator identification according to the preference order by using the assigned display mode.