The full rules are here: http://www.oneworld.com/documents/10...9-d346ec820edf

The restriction on city pairs is "The same city pairs/sectors cannot be flown more than once in the same direction". You don't breach that rule.

(It wasn't there in the dim and distant past, so I did HKG-NRT-HKG-NRT-HKG as my Asia segments many years ago, but that wouldn't be allowed now.)