You're free to choose the features you want when posting a new thread. However, since you represent a well-established brand (as you said), you should be aware that posting a self-moderated thread as an official ANN channel is unethical and raises many red flags that might discourage users from joining the site.

If there are posts you consider spam that could taint your ANN, there's a "report to mods" feature you can use to report it to the moderators, and I'm confident they'll make the right decision.