Driss Takir, Joshua Emery, et al. "Late Accretion of Ceres-like Asteroids and Their Implantation into the Outer Main Belt" is now published and linked around Space Twitter.
Although queen Ceres is at 2.8 AU from the Sun, several more asteroids exist of that (very dark) spectral type, between 3.0-3.2 AU... mostly. These include some you've heard of, like Hygiea the fourth-biggest. Dr Kirkwood imposes his famous 2:1 gap at 3.279 AU, for everybody; outside that, Cybele (herein reclassified) lives at 3.4 AU. Here also lives "Rosetta comet" 67P/Churyumov-Gerasimenko at semimajor 3.463 AU also, remember, inclination 7° (contrast Oort-origin retrogrades like Halley). Jupiter's moon Himalia is further of this type.
The spectrum is, per Rosetta, consistent with ammonia salts. Those could form only in Centaur distances, past Jupiter. As salts they won't boil off anymore down at 2.8 AU on up.
This pileup of Cereslikes in the outer Belt, and of an actual Jovian moon, reinforces theories of Ceres being brought into the Belt alongside those others. They are all comets, in a way; or, at least, once were.
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