After Jones' departure, the most likely replacement seemed to be original Killswitch singer Jesse Leach, who had sung with the band on a recent tour when Jones had to sit out for personal reasons.
While the band hasn't ruled out that possibility, it seems they're taking their time locating a new singer and have posted the following message on their website:
"We’ve been getting a lot of inquiries about the KsE singer position. If you are interested, please send an MP3 or a song link, a photo and a brief description of yourself to the management email address provided in the contact section."
So if you think you're the right person to fill Howard Jones' shoes in Killswitch Engage, you know what to do!