Andrew Dunbar wrote:

> Specifically I have read that China officially
> introduced the simplified character reform in two
> phases in 1956 and 1964. However, I have been unable
> to find any more detailed report. [...]

As others told you, the simplification process was not carried on in a very
transparent way, and probably it won't be easy to find the original
documents -- provided they exist.

I read a book whose co-author, Yin Binyong, an aged Chinese linguist, acted
as an advisor in some phases of the Chinese simplification process. Although
the book is not specifically about simplification, it gives some insight as
on how it happened.

BTW, it may be interesting for the computer geeks that it also contain
similar insight about the formation of GB character sets, as Yin was also a
consultant for Chinese standardization bodies that designed them.

Yin Binyong, John S. Rosenhow,
"Modern Chinese Characters",
Sinolingua, Beijing, 1994,
ISBN 7-80052-167-2, 0-8351-2474-6

If you can't find it in libraries or bookshop, I can see if I can scan the
relevant pages for you. (But I'll be away for at least two weeks now, and
probably I won't able to do it before January.)