Che Guevara!!
We didn't gain 6 days off by the new FTL. With the old FTL a day off was a 36 hours long; however, with the new FTL a single day off is 34 hours; therefore, with a simple calculation:
8 (days off) X 12 (months) X 36 = 3456 hours
8 (days off) X 13 (rosters) X 34 = 3536 hours
----------------
Difference is: 80 hours
Which are 2 days off (each 34 hrs long) and 12 hours; So by reducing 2 days from the leave bank, you can call it a gain of 12 hours!!!
Congratulations.....
rgrds