Actually it should be a clue to you that a day in the creation account does not mean a 24 hour day as we know it. Chapter 2 is a recap or summary of the creation. Since you seem set on figuring they might have sinned after the 7th day .. and do not want to consider that each day of creation is not a 24 hour period and the seventh day was not said to have ended while the other six days had a beginning and an end I guess we can leave the conversation. I enjoyed going over the biblical information with you even though it seems you're not willing to accept that the first 6 days of creation had a beginning and an end but the 7th does not have an end.
I'm perfectly fine with the idea that the days of Genesis are not literal. You're projecting things onto me that I didn't say. If you believe that the seven days in Genesis 1 can be "summarized" as a single day in the next narrative, then it shouldn't matter so much to you what happened on this day or that anyway. My point was simply that the text doesn't say. Which is true.