1 more thing you might want to mention is when you do the self address envelope and have it weighed for correct postage tell the postal worker that it can not be dated I had a few that when i went to the post office to mail them back they told me they were done wrong but he took them anyway. Grub your post office was one that did it wrong and there was another just dont remember whos. just wanted to mention this so FF doesnt have any problems mailing them back. all the ones that people did online where good.
JJ