With a 364 day calendar the 14th and 15th would always be on Saturday and Sunday. There could be a leap year every 7 years to add the lost days.
The above is where you are mistaken and, (like most futurists) you are essentially denying the work of YHWH and His Messiah at Golgotha because you are ignoring or rejecting the passages that were already quoted in this thread as having been fulfilled in the Messiah:
Isaiah 24:17-20 KJV
17. Fear, and the pit, and the snare, are upon thee, O inhabitant of the earth.
18. And it shall come to pass, that he who fleeth from the noise of the fear shall fall into the pit; and he that cometh up out of the midst of the pit shall be taken in the snare: for the windows from on high are open, and the foundations of the earth do shake.
19. The earth is utterly broken down, the earth is clean dissolved, the earth is moved exceedingly.
20. The earth shall reel to and fro like a drunkard, and shall be removed like a cottage; and the transgression thereof shall be heavy upon it; and it shall fall, and not rise again.
Amos 8:9-10 KJV
9. And it shall come to pass in that day, saith the Lord God, that I will cause the sun to go down at noon, [Matthew 27:45] and I will darken the earth in the clear day:
10. And I will turn your feasts into mourning, and all your songs into lamentation; and I will bring up sackcloth upon all loins, and baldness upon every head; and I will make it as the mourning of an only son, and the end thereof as a bitter day.
There was no need for leap years or extra days before Golgotha because the year was exactly three hundred and sixty-four days, as previously stated, and as witnessed in both 1Enoch, (the book of the luminaries which also has already been referenced herein) and the book of Jubilees from which you yourself have already quoted. Three hundred sixty-four days are exactly fifty-two weeks, which are exactly fifty-two Sabbaths, and every year ended with the final Shabbat of the year. Thus fourteen Abib was always the second Shabbat of the new year and fell two weeks from the vernal equinox which was the first day of the new year. The calendar was exactly as the Essenes explain it and they surely knew what they spoke of concerning such things. The events of Golgotha are what changed the length of the day.
This is the true length of the ancient day:
18 hours x 80 minutes = 1440 minutes (sundial clock)
24 hours x 60 minutes = 1440 minutes (modern clock)
This is the true length of the year:
364 days x 1440 minutes = 524160 minutes
However the length of the day is not 1440 minutes anymore because the earth no longer takes that amount of time to make a full revolution on its axis. The sidereal day is nearly five minutes short of 1440 minutes while the time it takes for the earth to make a revolution around the sun remains the full 524160 minutes in a year. The days are divided into the same amount of minutes per year but the days are not a full twenty-four hours:
524160 minutes / 365.24235 days = 1435.1019 minutes per sidereal day
1435.1019 minutes / 24 hours = 59.7959 minutes per hour in a sidereal day
1435.1019 minutes / 60 minutes = 23.9183 hours per sidereal day
1440 minutes - 1435.1019 minutes = 4.8981 minutes
The modern sidereal day is short from the true day by about 4.9 minutes and this is the reason why the year is now 365.24235 days instead of an even 364 days. Those changes are due to the minor axial pole shift which occurred at Golgotha when the sun was brought down at midday, (Isaiah 24:19-20 and Amos 8:9-10 which are merely two of the many passages which were fulfilled in that Great Day of Atonement that futurists often deny). In addition there is no other natural physical explanation for darkness over all the land from the sixth hour to the ninth hour as even a total solar eclipse generally only lasts somewhere from six to eight minutes. Depending on whether or not the statement "from the sixth hour to the ninth hour" is inclusive of the sixth and the ninth the full amount of time is from a fourth to a third of the day, (either three or four hours of a twelve hour day). The extra day and a fourth now added to the modern calendar are the fingerprints of the work of God at Golgotha written into your modern calendar into the ages of the ages and as long as the earth endures.