You will eat the oldest of what is old, and, when what is new arrives, you will throw away what is old
Other versions
King James Version
And ye shall eat old store, and bring forth the old because of the new.English Standard Version
You shall eat old store long kept, and you shall clear out the old to make way for the new.New International Version
You will still be eating last year's harvest when you will have to move it out to make room for the new.