src-redefine.5.a.c: 'aa....aa' does not have a 'base' attribute that refers to the redefined element, 'bb....bb'. <simpleType> children of <redefine> elements must have <restriction> descendants, with 'base' attributes that refer to themselves.

aa....aa does not have a base attribute that references the redefined element bb....bb. The simpleType children of the redefine element must have restriction descendants with base attributes that reference themselves.