I have had the same tactic used against me during regular season games. If I had seen there were only two LHP ready for the game, I would assume that the RHP would not start the game (even if they drop down as the starter). Sure enough, the robot substituted the ready starter.
I always check my opponent's staff to see who is actually available for each game. If a tired starter is listed, I know it will change. The only problem...if there are ready starters, both RHP and LHP...the robot could pick. Usually the robot picks the best available starter...given a choice. When the robot has both handed starters available, I make my prediction and set my line-up accordingly (sometimes I will use my most ambidextrous lineup anyhow).