In the Ivy file for Play's sbt-plugin for 2.3.5, one dependency is:

<dependency org="sbt-run-support-210" name="sbt-run-support-210_2.10" rev="0.1-SNAPSHOT" conf="compile->default(compile)"/>

There are a few issues with this:

1. Snapshot releases are not good practice, builds may not be reproducible.
2. The sbt-run-support-210_2.10 artifacts are in the Typesafe snapshots repo, and this may cause build failures for people who use a Nexus server as a proxy, and have not included the repository.
3. sbt-run-support-210_2.10 does not follow best practices for the groupId.

While it's up to you to decide whether to make a Play 2.3.6 release... the current setup is not ideal.