Unfortunately, the answer to that question is associated with a huge amount of uncertainty, not based on the lack of information but because various experiments have shown that the engineered salmon can have influences under certain conditions and be at a disadvantage under other conditions. So to try to integrate all that information into a net effect as to what would occur in nature is very difficult, and because of that, the uncertainty is large and that was taken into account in the risk assessment.
However, to answer your question, under certain conditions, with the escape of a fast-growing, voraciously feeding salmon in particular environments, the committee felt there could be effects on populations in the ecosystem of either competitors or Atlantic salmon themselves. So it is possible, but the overriding decision was that the confinement was massive and that there was not going to be an escape.
I should point out that there are no plans to grow these kinds of fish outside land-based, contained facilities, so they would not be in net pens where escape would be much more likely. That's the main objective at this time.