I've been trying to understand the algorithm framework and tested the attached code with the most basic parts:

  • ManualUniverseSelection consisting of only one SPY security
  • ConstantAlphaModel to emit a long signal
  • EqualWeightingPortfolioConstructionModel
  • ImmediateExecutionModel
  • NullRiskManagementModel

What I'm expecting from the backtest is one buy order at the start. However, there seems to be an extra order created a few days after the first order is filled. May I understand which module is creating this extra order?