Why do airlines consistently give triple or quadruple alphanumeric callsigns? They may trip off the tongue in the Ops dept. but we are obliged to say 'ABC wun wun wun' not 'ABC triple wun'.
On the plus side, one UK airline of an orange persuasion is pretty quick at changing callsigns if there is confusion - I phoned them up about a similar callsign at a similar time and they promised to change it immediately - never had the problem again.