Full text from SAG-AFTRA:
You cannot participate in conventions on behalf of or to promote companies we are striking against. This includes appearances, panels, fan meet and greets, etc. involving projects produced by struck companies, whether current or past, and current and past independent projects that are not signed to an interim agreement.
You may participate in a convention in ways that are wholly independent of your work on struck projects and that are not sponsored by or connected to struck companies. Additionally, you may participate in appearances, conventions, and fan expos for work under contracts other than the TV and Theatrical Agreements, such as TV or New Media animation or video games. (Theatrical animation is struck work and you cannot participate in events relating to animated theatrical content during the strike.)
Makes sense. I feel like Trek fans keeps getting screwed over with Cons lately though. Remember the con where they told the UK Discovery was still on Netflix only to pull it a few days later?