The bot in Lazy A (La) does not prioritize cargo traffic on the main line (2). Even when trains in the yard still have a red signal, cargo traffic on the main line is also stopped.
During certain times in Lazy you have to send cargo traffic on both track 2 and 224, which in this case causes congestion as the bot is not cooperating. I've noticed it now several times when dispatching in Lazy (Lb).