According to the latest intel, it'll live out the rest of its lifecycle until around 2019, but then drive off to its own funeral like so many limousines and hearses that were built off its platform. This was learned based on comments made by Cadillac chief Johan de Nysschen at the closed-door unveiling of the CT6 in Manhattan: "Ultimately, a car like XTS when it reaches the end of its lifecycle, will not be replaced."
That'll be bad news for the livery business that – in the post-Town Car era – has come to rely on the XTS as the basis for its stretch jobs. "We will not have a car that will lend itself to these kind of modifications and we will probably withdraw from those markets," de Nysschen told GM Inside News.
That's not all the new Cadillac boss had to say, though: he also indicated that the replacements for the ATS and CTS will be positioned differently from the current models: "As we move into the future refining our sedan portfolio, there will be no direct successor to the CTS. There will be no direct successor to the ATS. There is no point to renaming those cars because in the future those cars will disappear."
Based on Johan's comments and those we've heard until now, we'd expect the replacement for the ATS to move down a size to take on the likes of the Audi A3 and Mercedes CLA, and the CTS' successor to move down half a size class as well to give the new CT6 a bit more breathing room, and possibly an even larger flagship sedan to be positioned above them all.