The first Unity 2018 LTS release is now officially available! https://unity3d.com/unity/qa/lts-releases?version=2018.4

In an earlier Canny post, it was mentioned that upgrading to the 2018 LTS would be a priority: https://vrchat.canny.io/feature-requests/p/update-to-unity-2018-lts

I think upgrading the game to Unity 2018 would bring a lot of new possibilities to the table, such as the Jobs system, Progressive lightmapper on the GPU, cloth performance fixes, and much more. Please look into upgrading.