I have not started a new forum recently, and am a little confused by the results I see when I search for the term "trial period". It seems there are two possibilities.
Either you are seeing a notice indicating when adverts will start to appear on your site or you may have selected an "Adult content" forum . See the post at:
http://support.nabble.com/Adult-Content-is-NOT-free-anymore-td7584659.htmlHopefully, Nabble's Pedro will explain the different trial period lengths and the circumstances that control when each appears.
Volunteer Helper - but recommending that users move off the platform!
Once the admin for GregHelp now deleted.