Just a guess fm my own, it could be due to the PP deployment shape which is single folded and would be more comfortable to the wearer if the long end of the strap is pointing in the opposite direction.
IMHO, No watch can be better and more precious than a hand down item(watch) from the parents. Looks absolutely stunning, the older Royal Oak perpetual without the leap year indicator has a cleaner charming look and more vintage vibe. Wear and enjoy this watch in best of health
Thank you for sharing the beautiful photo of the RO Perpetual. Absolutely adore AP perpetual calendar. Is this the current production model of the REF: 26574 which has the contrasting blue dial vs sub dials? Finding quite hard to notice the differences on the dial that was replaced by the latest pro