If the days in Genesis 1 were not 24hour periods than the same hebrew word for "day" here implies that we're all to work 6 days (could be 1000 years per day?) and then rest for how long?

8Remember the sabbath day, and keep it holy. 9Six days you shall labor and do all your work. 10But the seventh day is a sabbath to the Lord your God; you shall not do any work—you, your son or your daughter, your male or female slave, your livestock, or the alien resident in your towns. 11For in six days the Lord made heaven and earth, the sea, and all that is in them, but rested the seventh day; therefore the Lord blessed the sabbath day and consecrated it.