Apparently (one never knows...), Blogger canceled the new full nudity policy and moved back to the old requirements (adult warning at the site entrance, no porn ads, etc). Interestingly, it mentions in the statement referred above "(it was) a policy change that impacts longstanding blogs": yes, that was me!
Therefore, thanks for the interest in being invited to the private blog but it will not be necessary: Becky and Trisha, the blog symbols, will continue to appear in public...
. (and thanks to the reader who warned me about Blogger policy reversal)