Not necessarily. The main indicator is what space the files are in;
for Draw, the ones in Drafts have not had image updates done, while
the ones in Reviewed have been updated.
Modification dates may have changed for files I checked out, made some
minor changes, decided I didn't have time to finish, and checked back
in again with a note of things remaining to be done.
For some other books (Getting Started, Writer, Calc), files in
Reviewed or even Published may need image updates because that didn't
get done for the first edition.
--Jean