Are you sure? I went to book my slot the second the AC invite was sent, and the latest date was 6 Feb. Also, ive spoke to a lot of people and that is also the latest date ive seen/heard.They have them all the way through until the end of March, but have sent out all of the invites already I think.
And they are non-rolling, so the fact they told us we could hear back in the next few days means it was the last one (as they dont send out any offers until all ACs are finished)