Second Version of "The Bell Jar"?

[Graveyard Dweller]

I seem to remember reading somewhere that Sylvia Plath planned on writing a second version of "The Bell Jar". The first version was written from the view of the protagonist while she was inside of the bell jar. The second version was going to be written from the view of the protagonist from outside of the bell jar. Has anyone else heard this, if so can you reference it. I'm afraid might have misread some biographical information, but I'm hoping I haven't.