packing in S⁳: what are the defects like?

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If you pack hundreds of equal disks in $S^2$, typically you get hexagonal close-packing with twelve defects (points with five-fold local symmetry, rather than six-fold) corresponding to the vertices of an icosahedron.

I would guess that a packing of thousands of equal balls in $S^3$ typically has regions of face-centred cubic lattice; but what are the defects like? Are they concentrated at the vertices of a {3,3,5} or {3,4,3} polytope, or along its edges, or what?