In EPiServer 4.62, it is only possible to schedule all mirroring channels to run at the same time. There are several scenarios where it would be much better to schedule individual channels differently. E.g. mirroring to 2 different servers and one server is offline for an extended period, so the channel should be suspended. Or mirroring to one server as a backup, and another for content syndication - the update frequencies could be completely different.