The Feast of Unleavened Bread is a seven day long feast/festival, where no leaven is to be within the household. Passover is actually the first meal of this week-long “Moed” (Appointed Time), as it is eaten after sunset on the 14th of Abib/Nissan. Sunset ends the day in YHWH’s reckoning of time, so the 15th day of the month begins in time for the Passover meal. The first and seventh days are “High Sabbaths”, where no work is to be done.