it was on their original list.
The other side of this is that other carriers could decide to add service from WN's other focus cities/hubs such as HOU and MDW. AA and DL both serve HOU, IIRC, but they certainly could add more service.
DL pilots are being told to expect a very aggressive summer flight schedule which hasn't been finalized. I'm not sure how many new routes that haven't been added might be added but there is very much the expectation that DL will increase frequencies and gauge in existing markets.
While WN is definitely going to be able to start a number of new routes over the next six months, their ability to defend their existing network will be stretched to the limit, in part because they have so few airplanes available.
The latest traffic report again shows WN's trips flown down by 6-7%. WN will have to shift resources away from its existing network in order to support all of this additional flying. That will create opportunities for other carriers including the legacy carriers that might be shut out of the AA/US divestiture markets/assets.