No relationship. The Lod is just where units are going to "line up" after preliminary instructions before they actually launch the attack (successfully implement the Op Sheet with Attack orders).
Now that I think of it once again, I don't get it. If LD has to do with preliminary instructions and linning up for the advance, I don't understand the following (shown in the example opsheets)
Return to LD and await new orders.
Rally Point: 14.05
Why should units return to LD instead of the Rally Point as dictated by the rules ? This does not make sense unless the Rally Point is somehow near or in the LoD