Flex Climb Thrust
I'm not aware of any users of Flex Climb Thrust, BUT, various levels of Derated Climb thrust are used in some aircraft.
For Example - The RR Trent uses CLB, CLB1, and CLB2, different ratings and pilot selectable. Above 10000 feet, all of these 3 become the same at full Climb Thrust (CLB).
Other operators may vary......