Maybe Seven couldn’t have predicted the major casting changes that Nine would make to Today, but they definitely would’ve been aware about the status of the Australian Open broadcasts since (at least) June 25 when it was publicly announced that Nine would have them from 2019.
I personally don’t doubt that Seven would’ve been aiming to have the full Sunrise presenting team on board during the Australian Open, regardless of whether or not the network has the rights to show the tennis.
Yes I’ve seen it quite a few times, but despite switching over to Today half a dozen times or more, haven’t seen any promos there for their new line up.