Both names/abbreviation make perfect sense IMO, but I believe that the majority here, including me has been accustomed to the abbreviation BTT, while the last two later “T” makes it even easier to pronounce; Therefore it will be nice to continue with the Abbreviation BTT because changing to BCT will have to take people some amount of time to master, we will even see a situation where people will still be writing BTT instead of BCT or even write BTC.