Stops a running campaign. A call already in progress is left to finish; no further numbers are dialled.

Starts a campaign, resumes a stopped one, or runs a finished one again. Which of the three happens follows from the campaign's own status, so the caller has nothing to pass: a stopped campaign continues where it left off, a finished one has its registry reset first, and one that is already running is left alone — the dialling chain picks up the next number by itself once the current call ends. POST