AFAIK, no there is not a pi3-kernel specific for UC16. However there is for UC18 if you upgrade to that, but all the pi kernels are published under pi-kernel for UC18 are under various tracks for the different pi’s on UC18 (i.e. there’s a pi-kernel track for 18-pi3, 18-pi2, and 18-cm3).
Not yet unfortunately, when this happens I’m not sure if one will be published for use with UC16, I imagine it will probably only be available for UC18, but the closest we have yet is @ogra’s work at Support for Raspberry Pi 4 - #14 by ogra which is unofficial and for development/prototyping only.