Since there seems to be unanimous support so far, I did a brief calculation of recent turn times to determine the optimal amount to set the timer back.
One occurrence of 27 hours, which I assume was a rare occasion where everyone finished before the timer ran out. Apart from that, nothing shorter than 29.5 hours. One 30 hour turn, and two 30.5 hour turns. The most recent 30.5 hour turn I know for a fact was about the true length of the turn because I played BGN/Catwalk's turn right after the clock would have ticked to zero. All the turns longer than 31 hours were presumably a result of pauses.
So, 30 real-time hours to 24 Pitboss hours seems pretty close to the mark. Conclusion: adjust the timer down by a factor of 20%.
Ideal new timer: 19 hours.
Given that most of the time delay is not a result of Pitboss clock timekeeping issues but due to unavoidable pauses during player logins, most of the ~5.5-6.5 hour delay will remain regardless of the timer settings. So this should work out pretty neatly to ~24.5 real time hours, plus or minus 30 minutes. In the unlikely event it falls a few minutes short of 24 hours, it's easy enough to pause to allow the 24 real-time hours to pass.
If we can get the turn flip time lagging by less than an hour or so each day, most of the time I should be able to reliably play any remaining turns within half an hour of the clock running out. That means instead of 4 turns per week, you should usually get 7 (occasionally 6). Sound good?