Start on page xi, "table of contents" I gave you the exact term and it has 2 pages on op code 06h. I will leave you to click around on all the tables and references. Working draft just means they will take suggestions on the specification. They then roll the suggestions in to the next ATA number and put it out as a working draft again. It does not mean the the actual specification is still in draft. It is a pretty common academic process.