Originally Posted by
Often1
Multiple Reservations. Southwest prohibits multiple reservations for the same Passenger departing from the same city on the same date. Furthermore, without notice to the Passenger or purchaser, Southwest may cancel such reservations or any other reservations that it believes, in its sole discretion, were made without intent to travel.
This language has been in there for a while. There was/is other language about speculative reservations which was ambiguous and could apply to reservation on different days.