Atlas is behind schedule on 7 locomotives, 4 Master and 3 Trainman. The Trainman Dash 8 40CW's have been pushed back again to 4th quarter of this year. That model is going on 7 years since it was first announced.
The 2016 (July - December) All Scales Catalog should be out this month so that might shed some light on the arrival of other models.
I get the impression that Atlas is going to do everything they can to get the California Zephyr trains and F3's delivered before the end of this year, even at the expense of other long overdue items.
I would be amazed to see any new locomotive announcements in the new catalog given the backlog. If there are any I wouldn't count on seeing any of them until 2018 at the earliest.