I believe the section which describes the number of digital blocks is incorrect, including the diagram. It appears to have been copied from the C27 documentation without revision.
3.2 Digital System
The Digital System is composed of 8 digital PSoC blocks. Each
block is an 8-bit resource that can be used alone or combined
with other blocks to form 8, 16, 24, and 32-bit peripherals, which
are called user module references.
When I cloned my project from a C27 to a C29 I discovered that the C29 has 16 digital blocks.