Me or my parents didn't get any ghost emails. They have a valid visitor visa and have visited Canada 4-5 times since 2015. The UCI # on PGP Medical and Bio request is the same as that was on their Visitor Visa Sticker. It is the same as on line 6 (CBN) and next to the text "PROPERTY OF THE GOVT OF CANADA". I hope this helps those searching for UCI # on a visitor visa sticker