The article is not using the term common type rating as it would be applied in the US. As a example a pilot typed on the 757 gets a 757/767 type rating and can fly either aircraft without additional training. He can also update his currency on both aircraft by getting landings in either aircraft. That is a true common type rating. All that has been approved for the A350 is a type rating can be awarded via a difference course. Landing currency must be established in each aircraft and does not transfer. For this reason Delta will not combine A330 and A350 flying.