From the time of Moses to the time of Yahushua, didn’t the Israelites keep accurate records of the seven-day cycle and the Sabbath?

Answer: The Scriptures tell us in over 200 verses that the faithful Hebrews kept track of the Sabbath according to the New Moon. They kept track only until they became unfaithful and were then taken into captivity by the Babylonians.  They remained in Babylon for approximately 70 years.  Then Yahuwah raised up Ezra and Nehemiah to restore Israel not only to their home land, but also to the truths of His Laws, Sanctuary services, and His true calendation.  This was why they were the restorers of the breach.  Every divine institution was to be restored, just as in the end time, one stone of truth upon another.

For as the new heavens and the new earth, which I will make, shall remain before me, saith Yahuwah, so shall your seed and your name remain.  And it shall come to pass, that from one new moon to another, and from one Sabbath to another, shall all flesh come to worship before me, saith Yahuwah.  Isaiah 66:22-23 KJV