You’re right, Java 9 support requires Eclipse Oxygen. In fact, it’s still not a part of the current Oxygen stable release, and will probably be included by default with Oxygen 1a, due in October.
2017 will continue to be Neon based, while MyEclipse 2018 is going to be based on Oxygen, so that’s the version to look out for, for Java 9 support. As far as timing is concerned, I cannot commit to a date right now, but it could be a couple of months out. Will update this post when more details are available.