When did Steem make it possible to edit old posts?

For a long time, I had the understanding that you could edit Steemit posts for seven days until it was "finalized" and went into the blockchain and impossible to change forever... But, today, I suddenly noticed that I was able to edit my old posts as well, some of them several months old. How come?

When did this change come? Maybe I am not paying enough attention to what's going on here on Steemit, but at least I am curious to learn more about it...

It is very positive that you can change old posts because in that way, you can remove content that you do not like, or information that isn't correct anymore. That is a great feature, especially when it comes to writing about VPN services like I do, because what I write today about VPN providers that will help you get access to Netflix in Canada might not work tomorrow. As a result, it is great that you can actually turn back time and make changes to old articles.

But, at the same time... one of the warnings I read before starting to write on Steemit was to think twice before you share information, because once it is shared, you cannot change it. As a result, it is written in stone, and it is there to remain public forever. That is a scary thought, but it was also one of the many charms with Steemit and how the information was recorded in the public blockchain forever and ever.

But, now it seems to have changed. When did it happen? Can I now edit my articles forever and ever? I hope someone can bring some light into this situation and teach me whatever needs to be taught for me to understand this!