This is another example of inconsistency. I had one flight I had to call about, then the next one was automatic and I received the e-mail sometime in the middle of the night on the 7th day in advance of my flight. However, I received no seat assignment, so I had to call, because it was a "old" Sabre reservation made prior to the May 21 transition. You cannot do seat selection online with a Sabre reservation (that I know of.)