Re: More than 300 dead is largely worth an abundance of caution
They have not yet completed the investigation into the Lion air crash so have not yet issued any recommendations.
As I understand the crash investigation process, investigators are obliged to produce an interim report 12 months after starting the investigation. They will then produce a final report when they are ready.
If there is something glaringly obvious produced before the either of these reports, they may publish an alert bulleting before this.