Plat, waiting to become Plat4Life in April and it has happened to me last week, for the first time in the last 10 years +. A regular "la navette" flight, inbound in Flex, return in Smart. Row 1 for the first flight, no option to get better than row 10 for the return (far from being full at the end) :-(
Ultimate is (I hope) probably helping in maintaining that perk. But if they want to run the company only counting on Ultimate profile, they'll be a bit short...
Tonin