Rubbish. ATC lined up a Rex at Foxtrot intersection after already having told AirAsia to line up full length and that their would be a " midfield " departure before they got going from the full length. Rex were cleared for take-off as JQ were on a short final. As rex rolled there was obviously no time to get AirAsia off as well so JQ were told to go around. AirAsia were cleared for takeoff with an amended 3000 limit. Shortly after takeoff the AirAsia was told to maintain HDG 160. They complied. They were then recleared to a higher altitude and told to contact Departures. While JQ were going around AirAsia asked Tower to confirm that they had indeed been cleared to lineup. I reckon they could see what was going to unfold.