sorano916 said: "If swings don't receive additional compensation when they go one in an ensemble role, do they if it's a split track? Or vice versa, when a single regular track is split into three tracks?
For example, in Les Mis, actor Joe Spieldenner is in the ensemble, with featured tracks of Grantaire & Bamatabois. When he's out, three different people are listed in those tracks: one for Grantaire, one for Bamatabois, and one for his ensemble (aka just "John Doe" is on for "Joseph Spieldenner".
All the helpful replies you're getting to your question are accurate. A swing or ensemble member covering an ensemble role does not get extra pay for going on. If three people cover one absent ensemble member's roles (for a particular performance), none of them get a bump. If one person goes on for all three of those (ensemble) roles, he still doesn't get a bump. Swings and ensemble members DO get (a little) extra pay every week for the duty of understudying an ensemble role. I think it's $15 a week, for every role you cover - whether or not you ever go on.