Why does the last creative day have to be such a rounded number?
Why can't it be 7092 years long? 7601 years long? 19283 years long?
WT look for number patterns that land in the current timeframe and try to make them fit a baseless interpretation. WT decide on a date and then try to justify it.
None of this has any credence beyond a weak "but it would make sense if...".
Bottom line is, no matter how convinced you are, there's simply no evidence for a creative day being one duration rather than any other duration.