I think you are right that it is an earlier model. I found a discussion online with the older part number, and the info was from several years back. The older version may have the "pin" style fence, the current version has the "paddle" style. Either works just fine.

Here is a picture of mine with the paddle style fence, earlier models had round pins instead. These are used to index off of various edges or adjacent mortises instead of making a bunch of lines with a pencil.

 

Here is the older style pin fence, FYI:

 

Thank you very much

 

You bet. And if you are not already, check out the FOG, Festool Owners Group forum online:

http://festoolownersgroup.com/