Change my mind!

From the update notes:

The deployment area of the first round has been expanded forward by 20m, and now it is consistent with subsequent rounds.

Developer's Note: In the past, to battle the random nature of round 1, we reduced the deployable area of round 1 by 20m. After introducing the building layout, we can now remove this special rule.

Also see summary on reddit: https://www.reddit.com/r/Mechabellum/comments/1loqxyf/bearlike_talks_about_new_changes_in_season_4/