"replacing AC & SM" my spider-sense is tingling they may never come back
That would actually make sense. CIG is probably more than stretched as it is, 600+ staff or not (did I read somewhere 700+?), to just cope with any PU/SQ42 roadmap they ve ever put out plus now supporting "dynamic" events, nevermind maintaining or improving 3 separate game modes on top of that. SM and AC have been long obsolete, not because CIG may have learned all it needs to learn from them as originally envisaged, doubt that has ever been of much use, but simply because they are as broken as the PU and just... well, suck.
Outsourcing it to someone else would just be the cherry on the cake to eventually free itself up from most obligations and manpower requirements, if not all, on all those game modes. Given firesprite timelines it is actually possible this may have already happened unannounced years ago.