No, it will keep the same arc ID and ratings. If you unpublish it, you will lose ratings and the arc ID.
[url="http://adingworld.wordpress.com/mission-architect-story-arcs/"][b]My Story arcs[/b][/url]: [i]The Siren Supremes[/i] ([b]1143[/b]), [i]The Missing Geneticist[/i] ([b]2542[/b]), [i]Elemental Jones[/i] ([b]263512[/b]), [i]The Soul Hunter[/i] ([b]294431[/b]), [i]Heart of Steel[/i] ([b]407104[/b]), [i]Project Serpens[/i] ([b]434082[/b])
If I edit a published arc, does it get a new id number?