You can see that they've already attempted to reinforce the retaining wall with those metal pylons. It's not a great fix as it's a bit of an eyesore, cuts down on the width of the road back there, and the wall is still leaning so this seems like a temporary fix at best. Cutting into the hillside by about 80 feet does add about an acre, a little bit less, to the available land. I would temper expectations, though. It's good planning for the future, for sure, as the Lower Lot is due for a major expansion once the soundstages between Mummy and TF are ready to come down, but I don't think that area will be anything usable for the park (except maybe the future location of an HHN maze) for a while, probably beyond the Olympics.