Two days ago, asked about the behaviour of the lighting system during the fireworks, the officials of the Jacques-Cartier bridge replied (@pontJCBridge): "Juste un éclairage fonctionnel pendant les feux mais un clin d'oeil à #Canada150 exceptionnellement le 1er juillet."
This morning, there are news reports that a 8-minute special sequence, made of red and white colours, will be performed from the sunset to 3am each hour, to celebrate Canada Day.
http://quebec.huffingtonpost.ca/2017/06/30/une-illumination-speciale-d u-pont-jacques-cartier-pour-la-fete-d_a_23010876/?ncid=tweetlnkcahpmg0 0000011
We will see if there's more for the countdown as reported by Paul.
Paul, about a Ian Kelly's live performance: this is advertised on La Ronde website since the September 2016 press conference. I have not heard anything else, though.
Fred