Obvious solution ~ just admit that when God handed down Genesis 1 He used a word to describe the vast periods of time involved but human beings later on, not understanding the enormity of that time period, simply misappropriated God's word to use for the period of Sundown to Sundown.
Not only that, they began using the word to describe the period of time from Midnight to Midnight, and we all know that's just not right.
Thomas Paine asked if God didn’t make the sun until the third day, then what exactly, were the first three “days”?