L29A CREW AT FL280 UNDERSTOOD AN ADVISORY TO BE A CLRNC AND INITIATED A CLB.

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JAN/XA/01 FLT PLAN RTE: JZI-SAV-CRG-OMN-BCT AT FL310. DEPARTED JZI AND RECEIVED CLRNC FROM CHS APCH CTL WITH AN EXPECTED ALT OF FL310. DURING THE ENRTE CLB SEGMENT; WE HAD RECEIVED A STAGE CLB TO FL280 WITH JAX APCH CTL. AFTER BEING ASSIGNED A RADAR VECTOR TO THE BEENO INTXN; WE RECEIVED WHAT WE UNDERSTOOD TO BE A CLB CLRNC TO FL290 (LATER LEARNED TO ACTUALLY HAVE BEEN A TA OF TFC AT FL290). AFTER THE COPLT (PNF) READ BACK 'CLB FL290; ACR X;' I (CAPT/PF) INITIATED THE CLB. AFTER THE CLB WAS INITIATED; AND AT APPROX FL284; ZJX REQUESTED THAT WE VERIFY LEVEL AT FL280. COPLT READ BACK THAT WE WERE ESTABLISHED IN A CLB TO FL290. ZJX THEN ISSUED THAT WE DSND BACK TO FL280. WE COMPLIED WITH THE DSCNT TO FL280 AND SHORTLY THEREAFTER WERE RECLRED TO FL310. UPON ARR AT THE DEST (BCT); I WAS ADVISED TO CALL ZJX DISPATCH. UPON SPEAKING WITH THEM; I WAS ADVISED THAT THE CLB TO FL290 HAD ACTUALLY BEEN A TA AND NOT A CLB CLRNC. APPARENTLY; WE HAD NOT RECEIVED THE ENTIRE TA IN QUESTION; AND CONSEQUENTLY INTERPED IT INSTEAD AS A CLB CLRNC. ZJX STATED THAT THE TAPE OF THE EVENT CONTAINED THE TA AND A PARTIAL READBACK OF OUR RESPONSE TO WHAT WE THOUGHT WAS A CLB CLRNC; AND THAT THE CTLR DID NOT CORRECT IT WITH RESPECT TO THE CLRNC IN QUESTION AS HE THOUGHT WE WERE ACKNOWLEDGING THE TA. HE (THE CTLR) DID NOT CORRECT US ON THE CLRNC UNTIL WE HAD APPARENTLY RAISED CONCERN WITH RESPECT TO SEPARATION FROM OTHER TFC (THE CTLR WAS SAID TO HAVE INTERPED OUR RESPONSE AS AN ACKNOWLEDGEMENT OF HIS TA). AS STATED PREVIOUSLY; I/WE COMPLIED WITH THE DSCNT BACK TO FL280 AND SHORTLY THEREAFTER RECLRED FOR THE REMAINDER OF THE CLB WITH NO FURTHER CONFLICT. THE COMBINATION OF RADIO NOISE; INTERFERENCE; INAUDIBLE XMISSION ON BOTH PARTIES (CTLR/PLTS) AND THE LACK OF THE CTLR CORRECTING US ON OUR READBACK (WHICH HE MAY HAVE QUESTIONED) LED TO THIS SIT. ADDITIONALLY; WE HAD BEEN EXPECTING THE CLB TO FL310 AND ANY OTHER INTERMEDIATE CLB WAS EXPECTED BY US. REMAINDER OF FLT PROGRESSED NORMALLY AND WE WERE ONLY MADE AWARE OF THIS ANOMALY AFTER LNDG AT THE DEST (BCT).