Hi Renos... I think when the piston rings are new and fitted to a rebored cylinder they must surely rotate to some extent until they find a place to rest and then bed in. When ever I have fitted rings they are always in a different place when cylinder is removed. I usually put the oil scraper ring join at the back of engine 6'o'clock, then middle one at 2'o'clock position and top ring at 10'o'clock. I would not think that the rings are rotation constantly, I maybe wrong though... Interesting question!