Other-I apologize but I have been unable to get an answer for you pertaining to the memo you reference.  I suggest you go to Air Force Material Command at http://www.afmc.af.mil/ and use the contact us button at the bottom of the page for assistance with your question.

I did do a web search using the keywords "payment of expenses to  obtain professional credentials" and found considerable information on the subject. You also may want to give that a try.