It looks like Finn is wearing either his medical shirt or the same type of shirt that Poe wears in The Force Awakens. I’m sure at Star Wars Celebration Orlando we will get an even better look at Rey and Finn. Justin was also able to see a 2018 The Last Jedi calendar at Toy Fair. Check out his description of what he saw:
— Justin LaSalata (@justinlasalata) February 18, 2017
I believe Justin is referring to Kelly Marie Tran’s character in The Last Jedi. He also confirmed later on that Luke is featured on the calendar. Thanks to Justin for all this awesome info!