I would be surprised if they got approval. Given that the Federal government initially tried to block US/AA from happening only to relent and then have fares go up, I do not see how this could happen. True, that US was a national carrier and AS is not, and I have not seen the data for AS/AA overlap recently, but just from an optics standpoint, I still think it would be very tough.
Additionally, the airline stocks are all high now because the companies are finally focusing on returning capital, so any deal would have to be accretive day 1, and not sure the math works.