Activision's restraint has been commendable. When a Modern Warfare remaster was announced last spring, it was tied to premium versions of Infinite Warfare. Most everyone assumed that a standalone release was inevitable, probably after residual Infinite Warfare sales had completely dried up. We've gone a year without any real indication from Activision that it would ever happen.
Finally, word of that standalone release is starting to kick up -- not from Activision, though. As reported by Call of Duty enthusiast site Charlie Intel, GameFly accidentally posted listings for the Modern Warfare remaster that put its release dates as June 20 on PlayStation 4 and July 20 on Xbox One. (The listings have since been taken down, but screenshots are in the gallery below.) This month-long headstart would perfectly mirror the 30-day advantage PS4 players had upon initial release.
Of course, it's entirely possible that this information could be slightly off. Retailers put up listings with placeholder dates all the time. But, the important thing is that GameFly even put up pages for this in the first place. Also, those dates seem awfully likely, especially considering most everyone thought a standalone release would've happened by now.
Activision hasn't yet commented on this. It's probably just a matter of time until we have confirmation, though. This always felt like a "when" rather than an "if."