Jubilee is not part of the cycle count per say. There is only the 49th counting of Sabbaths. Then the Sabbatical cycles start over. The Jubilee is celebrated after the 49th Sabbath year count. The Jubilee is on the 50th year but is counted towards the next 49 count cycle.
Yovel (Jubilee) Years
Another reason why Jubilee is not part of the sabbatical year count, the 'fiftieth year' that does not synchronise with the Sabbath years, does not start on the New Moon, and finishes at the wrong end of the calendar. The 50th year actually straddled the 49th and 1st years of the old and new cycles.
The first of the year is in March/April [Nissan 1] and the straddle Jubilee is from Yom Kippur to Yom Kippur [sometime in Sept/Oct]. Tishri 1 [Rosh Hashanna] is the start of the calendar year of the sacred calendar.
Ez 40:1 In the five and twentieth year of our captivity, in the beginning of the year, in the tenth day of the month, in the fourteenth year after that the city was smitten, in the selfsame day, the hand of the LORD was upon me, and He brought me thither.
We know that the Jews have two calendar years every year. One is the civil year and the other is the sacred year. One starts in the spring and one in the fall based on scripture where the Lord tells them that this is the start of the year.
Rosh Hashanah literally means "
beginning [of] the
year".
Ex 12:2 This month shall be for you the head of months, the first of the months of the year”
Nissan, the first month on Jewish calendar coincides with March-April on the civil calendar.