Ok.
Nobody answered my question.
so, I researched the block timestamps in Bitcoinwiki.
They say it may not exactly accurate.(Block times are accurate only to within an hour or two)
https://en.bitcoin.it/wiki/Block_timestampTimestamp order is not important.
My problem solved.
It's what I posted in my first response to you (clock drift) - it is working as intended. However, I don't recall seeing a 2 hour difference between specific blocks within the last 11 entries which is why I asked as well.