The gravitational field (curvature) of manifold patch, inside of outward expanding idealized spherical shell of matter, would be affected by newly formed 5 solar mass BH only. This is an example of
Newton's First Theorem: A body inside a spherical shell of matter is not gravitationally affected by mass of such spherical shell i.e. no gravitational force is felt. So gravitational field has changed for inside of spherical shell of neutrinos. In contrast, a body outside of such spherical shell, would feel gravitational force (i.e. curvature) as if all of mass were concentrated at center of such spherical shell. Thus 10 solar mass gravitational effect. Hence curvature (i.e. gravitational force) has not changed for outside of such shell. The latter is an example of
Newton's Second Theorem. See Shell Theorem.
http://en.wikipedia.org/wiki/Shell_theory Realistically only about 10% (?) of mass is carried off by neutrino symmetrical expanding shell.
Also the change in
distribution of mass would occur over a finite time (finite velocity); hence the
gravitational field (i.e. curvature, deformation of manifold) would change over a
finite time.
In regards to addendum: if Newton had been exposed to a clear ordinary glass with a spoon, stirrer etc. in it, his analytical mind probably would have surmised that velocity of light was finite; not infinite, since a change in velocity has occurred for a different medium.