Why are there clone troopers in The Old Republic trailer if they shouldnt exist for another 3621 years?

Ok so I may be just assuming theyre clones because you can only see one persons face, but that guy looks a hell of a lot like the other clones from the clone wars era. Even their armor looks identical.

Now, the Old Republic game takes place 3,653 BBY but, the clones werent ordered to be created by Sifo-Dyas on Kamino for another 3621 years in 32BBY.

Am I missing something somewhere in star wars history that explains this?

The only possible explination I can think of is they’re just other clones of a Mandalorian since they were active at this time as well which would explain why the armor looks similar, but I dont know, that guys face just looks too alike.

/nerd rant