Two alternative meanings.

1. A rota that runs through planned shutdowns. Its purposes is to show who would be called in, and when, if cover is required during the shutdown.
   Synonymous with: Holiday Rota
2. A rota that runs alongside the basic rota showing who is liable to be called in, and when, if there is a shortfall in staffing levels on a rostered shift.
   Synonymous with: Cover Rota, Call Out Rota, Stand-by Rota.