Can we assume that CoffeeScript will generally remain a superset of ES6 features? I'm trying to figure out if I should ditch coffee for 6to5 but won't bother i

Can we assume that CoffeeScript will generally remain a superset of ES6 features? I'm trying to figure out if I should ditch coffee for 6to5 but won't bother if coffee will give me all the ES6 features plus the easier syntax (no semicolons, fat arrows, etc).