SIMILAR SOUNDING A/N CAUSED THE FLC OF AN MLG TO PREMATURELY START TKOF AND THEN ABORT WHEN THEY DETERMINED THAT THE CLRNC WAS NOT FOR THEM.

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ON PREVIOUS FLT FROM DAL TO HOU; ACFT CALL SIGN WAS CHANGED BY COMPANY FROM FLT XX TO XY. AFTER MUCH CONFUSION AT GATE WITH CLRNC FLT PROCEEDED TO HOU AS XY. FROM HOU TO CRP ON THE SUBJECT FLT; THE CALL SIGN WAS CHANGED BACK TO THE ORIGINAL OF XX. CLRNC WAS RECEIVED AS XY AND FLT WAS CLRED TO TAXI OUT AND ON TO HOLD ON RWY 30L AS FLT XY. WHILE ON HOLD WE HEARD WHAT WE THOUGHT WAS FLT XX CLRED FOR TKOF; THE FO WAS FLYING AND THE CAPT RUNNING THE RADIOS RESPONDED FLT XX CLRED FOR TKOF. THE HDG ASSIGNED FOR DEP DID NOT SOUND CORRECT SO THE FO HAD THE CAPT VERIFY HDG FOR THE FLT; IT THEN BECAME APPARENT THAT FLT XY WAS NOT CLRED FOR TKOF BUT ANOTHER FLT ON ANOTHER RWY HOLDING FOR TKOF AT THE SAME TIME WAS THE FLT ACTUALLY CLRED FOR TKOF. THAT FLT NUMBER WAS XZ. WE ABORTED THE TKOF AND CLRED THE RWY AT TXWY L. RECOMMEND THE FLT CALL SIGNS ONCE CHANGED REMAIN CHANGED UNTIL THE COMPLETION OF THE FLT SEQUENCE AND THAT WHEN A FLT CALL SIGN IS CHANGED IT SHOULD BE ATTEMPTED TO MAKE IT DIFFERENT FROM FLTS OPERATING IN THE LCL AREA; IE; XX AND XZ NOT BEING A GOOD IDEA. ADDITIONAL NOTE: WE ROLLED APPROX 1000 FT BEFORE ABORTING THE TKOF AND THE OTHER ACFT FLT DID NOT START TKOF ROLL.