No writing down moves in advance of making, or in advance of completing Per FIDE rules, I must not write down moves "in advance".  Does this mean: in advance of making, or in advance of completing?

Today I have seen a strange ruling as a spectator.  A young player made a move, wrote it down and pressed the clock.  The other player called an arbiter and objected to the order of actions.  The arbiter seemed to be agreeing with the complaint, stating that the mandatory order is making the move, pressing the clock, and only then writing it down.  (It wasn't obvious whether this was meant as advisory or warning.)  This was in Europe.

I prefer answers based on non-US experience if available, because the USCF used to be more lenient toward writing down 1 move even immediately before making it, and that is hopefully irrelevant to my question.
Once a move has been made (hand has left the piece) the move cannot be changed unless it is an illegal move. 

The rule against writing the move down in advance is in relation to "taking notes". If this were allowed you could write down what you thought was the best move and then stop and think for another 10 minutes considering other possibilities. If you reject the other possibilities you don't have to worry about forgetting your original choice because you wrote it down. If half way through you see a better move than your original you can erase the original move and write the new move and continue thinking. It is this behaviour that the rule is aimed at stopping. 

In the case you saw the question does not arise because having made the move the player can't change the move. Writing the move down now whether it is before or after pressing the clock is not taking notes and is not against the rule. If the arbiter really thought his behaviour was against the rule and gave a warning then he was wrong.

I am a FIDE arbiter for an Asian country, currently living in Europe.