Owen Evans writes...
"Back in July when we launched the new ArcGIS StoryMaps we also announced an initial transition timeline for our classic storytelling templates (Story Map Journal, Cascade, Tour, etc.). Since then, we’ve been monitoring the usage of both the new and classic story builders and listening to the feedback we’ve received from our community of storytellers. Now that we’re a few months into this new project, we wanted to revisit this timeline."
Read more at Updated classic story map transition timeline