I see them closing 400 production for sure, price point of each is not far off and no sense competing against eachother.
People have been talking about a super Apex, basically waterproof and a few other whistles, I see them going the other route and come out with a cheaper detector in the $250-$300 range to make a play for the low end/budget market, which they currently don't have anything to fit that bill [unless they drop the price of the 400 below the simplex] Even then, the 400 is outmoded, very decent detector that it is. People want LCD display, back-light, adjustable volume and the 400 has none of the above. If they could add just those 3 things to the 400 and drop the price a bit, I think they'd have the low end locked up - They'll make a nice dent in midrange with the Apex, and maybe make a play for higher end next summer with an Apex Pro.
Don't see the AT going anywhere quick by virtue of it being a very capable hybrid water machine - Obviously, an introduction of an Apex Pro would be the death knell for the AT.