In the very first scene when Jake is being restrained by the army personnel, the flag on one man's arm is visible and while the new star pattern is visible, the stripes are still horizontal rather than vertical in the rest of the episode. The flag on Major Beck's arm, however, has the correct stripes.
In the beginning of season 2, the soldiers are wearing the new American Flag on their left shoulder with their unit patch (10th Mountain). The American flag is always worn on the right shoulder
The sound of the train horn is from a diesel locomotive, not a steam locomotive.