Incorrect English in "First blog post"

1. "Once you've clicked published once, you cannot unpublish a post."
You would click "publish" not "published"
also using "once" twice in a clause is a bit awkward.

May I suggest: "Once you have clicked publish, you cannot unpublish a post."

2. "A post can have one of the following statuses:"
Though it is technically correct, the word "statuses" is very uncommon and it doesn't flow easily.

May I suggest: "The status of a blog post may be any one of the following:"