I have no problem with rebranding your program. Your explanation that the program is the same but the name better reflects how the program has evolved makes sense. I suspect there are additional factors in this move and believe you should be honest about them. I suspect it has more to do with ego (Tippett's) and money (funders, market share, etc.) than content or ideas.
That said, I like the "On Being" part of the rebranding. I have serious problems with "Krista Tippett on Being." What makes this program great are its guests and CONVERSATIONS on faith, being and life. The literal meaning of the new name refers to the host's ideas / reflections / ruminations on Being. Even with the subtitle, the literal meaning of the first clause stands.
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