Looks like we have an arms race.
"Samsung Display originally planned to use the M8 for the Galaxy S9 for the long term and to use the M9 from the Galaxy Note 9 (tentative name) to be launched next fall. M9 originally submitted samples in November, the mass production validation schedule was set up until June next year. However, it shortened the development schedule by six months ahead of the existing plan.
The specs proposed by Samsung Display for M9 development to its partners are to keep the drive voltage at the current level, but to raise the life span and efficiency to sunlight level. In other words, it aims to equalize panel quality with iPhone 8 (tentative name) which will be released this fall."