So is there a chance it will be supported by "Stretch", or will it be
whatever comes after that?
If someone does the work there's no reason it couldn't make Stretch,
the freeze isn't until the second half of next year.
I guess the first step in "doing the work" would be tested patches to
enable the relevant drivers etc in the .config for the armmp package
filed as wishlist bugs against src:linux package, once trunk hits 4.4
if that's a prerequisite.
Likewise for the flash-kernel support.
The only sticking point I can see up front is many of the blobs in
/boot/firmware are non-free (right?), which means they can't really be
in Debian, only in the non-free repository, which has an impact on the
production of SD-card images and maybe d-i too, I suppose.