I think you must let them know change of your address as this can be considered misrepresentation that you have not informed of the change of address. thanks
B053 is not your bar code. its your file no. Bar code is mentioned on left side of your 2nd AOR file no. Have you got 2nd AOR? check on the left side of your 2nd AOR file no. it should be 013 or something like that
he clarified later 3 stands for that you will be recommended for medicals to be issued and its not related to your noc. thx
http://www.canadavisa.com/canada-immigration-discussion-board/chc-london-file-number-barcode-t61028.15.html