I've been playing with the edit beta mode in the playground using the alpha text-davinci-edit-001 model but it does not appear to be free as the article states: all the calls made to the edit endpoints were charged to my account.
As larger requests (ex: spellcheck or translate 1000 words) can cost 20c+ each and the model often requires to be ran 2 or 3 times before giving an acceptable answer on more complex tasks (ex: translation), that makes for a very expensive tool if you want to edit a significant amount of text.
I wonder if the free usage only apply to the Codex engine and not the GPT-3.