According to the official website, Kokoro Connect
was announced to be 17 episodes long. It's likely that Episodes 14 - 17 will be streamed online or Blu-ray only.
Source: Kokoro Connect official website
Update Sep 30
According to Kokoro Connect official Twitter account, episodes 14 - 17
will be first shown at a live event, followed by the Blu-ray releases in March and April.
Source: Kokoro Connect Anime Twitter