While they may not have the specific parts, it's entirely possible that they can and will support the manufacturing of some necessary replacement parts. They have acquired all the intillectual rights to the Coleman/Fleetwood popups, which means they should have the ability to manufacture them (or provide those details to another manufacturer).
Watching the video on their web site, I saw that they're using the same bunk rail slide extrusions and end-stops, both of which I know were a concern for those with existing Coleman/FW popups. Though the dimensions may be different for the new Somerset line, they could easily cut and drill the channel to fit a Coleman/FW trailer.
Things like the roof lift arms I have heard will be a little different due to the different roof the top-end attaches to. However, if customers need a set, I see no reason they couldn't make them to fit. Again, they have all the specs for the originals, why wouldn't they produce the parts for folks that need them?