According to Deadline, producers of the show Martin Moszkowicz and other members of the Constantin Film company are "amazed" by the fans dedication. "[We're] amazed by the dedication and persistence of the incredible fandom of Shadowhunters and the #SaveShadowhunters campaign. We are in ongoing discussions with the network and Netflix to [see] how we can continue to bring Cassandra Claire’s vision to television."
However, Netflix aren't 100% on board just yet. A rep from the company told Deadline, "No Netflix negotiations are taking place to extend Shadowhunters beyond the 12 new episodes planned to premiere in 2019."
Deadline also reported that Constantin Film have gotten "thousands of emails, tweets and Facebook messages from the fan group that’s self-organized via social media."
PERSISTENCE IS KEY!