DC
I cannot see any good reason why they would need a second copy of the letter, providing that the original one was received in good quality, but it does mean that the "action" is now on you in regard to progressing this matter.
Although they have not stated any other intent with regard to their getting the copy of the letter, I would recommend that you try and get their yourself, however, if it is easier for you to get a friend or relative to do this, then go that way. The requirement for an appointment is because they do not want claimants just turning up at the JC+ offices, so I would not read too much in to that.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems 
