Replacing Grontier is Matt Walst, frontman of My Darkest Days and brother of Three Days Grace’s bass guitar player Brad Walst. Currently, statements point to this being a temporary replacement just for the upcoming tour.
Here’s Matt Walst singing Three Days Grace’s new track, Chalk Outline:
And here’s the original with Adam Grontier on vocals:
I don’t think Walst does a bad job covering, but his voice just doesn’t have the same tones that Grontier does. If this becomes less temporary than indicated, it will definitely take some getting used to.