OK, so there is apparently something on the app that says 2017. Still that could be an error. I really need some sort official press release from Netflix or Marvel to affirm it's next year.
So let's put it like this. Hypothetically speaking. Defenders counts as extra since it's a shorter eight episode miniseries, so we can get a full season of another show. Here's how it could pan out.
2015 - Daredevil and Jessica Jones
2016 - Daredevil S2 and Luke Cage
2017 - Iron Fist, Defenders and Punisher
2018 - Daredevil S3 and Jessica Jones S2
2019 - ???
It's really just hard to see where they will go with this. Especially if they think about doing shows such as Moon Knight or Blade.