A Question for Attempts at Allegorical Interpretations of the Genesis Act

The Torah states that the people of Israel are commanded to rest on the seventh day, the Sabbath, because on the seventh day God completed the creation of the world. Likewise, it is clear that the way to reconcile the act of Genesis with the scientific knowledge we possess today about the age of the world, the billions, and evolution is through an allegorical interpretation of the "days" in Genesis 1 and the creations that were created in those "days." But in order to commemorate God's rest, the people of Israel were commanded and do observe the Sabbath every seven days, and not every 7,000 years or 1/7 billion years or something like that, which shows that the Torah did indeed intend that creation took six literal days and God rested on the seventh literal day. Doesn't this pose a serious problem for the attempts at allegorical interpretations of the beginning of the Book of Genesis?