CDNA Masks

Just a question with the number of Masks for CDNA in the sv2p_model.
You have a mask for each of the 10 Transformed outputs, another for a static background (masking the input image) and another for the output of the model, should that not be 12 masks, not 11? 
It seems as though you are not using one of the transformed outputs, or am I interpreting this wrong?
Thanks