I don’t remember if it was mentioned here on Retro or elsewhere, but one possible reason for 1103 still containing the pre-MJ tracks was that it may have been a prototype for the multiplayer feature (?) since the competition stuff was close to final as opposed to the main game. Perhaps the devs were separated into groups and worked on different portions of the game, thus there were separate builds? If the date is indeed true, think of all the crunch time the devs had to go through between 1103 and the final build. I don’t know how long it would take to substitute the tracks in question, but crunch time was most certainly a factor in going with the MJ/Buxer tracks. They could have wiped their slate clean as well by polishing up the replacement tracks and adding them prior to the release of Sonic & Knuckles to get it ready for the lock on stuff but alas it didn’t go down that way.