Ember Canyon, the first medium map with bases on top corners, had some issues with the starting building on the right. Some were placed one tile too far to the left, overlapping a starting truck. The additional map bundle was updated to include this fix.
Builder map pool change
The statistics shows that the Fighter league is played more than the Builder league. But when watching the replays, it looks like most players are playing closer to what should be expected in the Builder league. The games show a lot of initial trucks and battles starting between minute 5 and 10. They are more expected between minute 1 and 3 in the Fighter league, as you could experience against the AI.
The only difference between leagues is currently the name and the map pool. So to know if players join the Fighter league because of the name or the map pool, the later was updated to be closer to the one from the Fighter league. The stock maps Vision and Roughness were removed and the small maps High Ground Pass and Channel Docks were added.
The large maps are still more favoured in the Builder league. Even if the 30 seconds delay to reach the base is not that much, it still gives more room to pick derricks and spread on the map.