It's hard to say. Heath hasn't had a lot of screen time so either they will kill him off and not being his character any further or they will really start developing his character. I like Heath and wish he had more screen time. I hope he doesn't leave but it happens on this show.
Andrea is still alive in the comics too so that doesn't really mean much these days. The writers like to sway from the comic lines and character deaths. Hell even Morgan died during the zombie invasion in Alexandria but is still kicking on the show.