The laws of Yovel and Shmitah are only applicable to the land of Eretz Yisrael. Thus, prior to the Jewish people entering Eretz Yisrael in the year 2488, the laws did not apply. Further, the laws of Yovel only apply when all (most) of the Jewish people are settled in the Land. (Some commentators do count backwards to the Creation to establish “Yovel” years)
GOING OUT OF EGYPT
Nisan 2448 1st
INITIAL SET-UP OF THE MISHKAN
Nisan 2449 10th
ENTERING ERETZ YISROEL
Nisan 2488
FIRST YEAR OF SHMITAH COUNT
2504