This always seems to happen to me. "I hope there isn't an update today because I just need to quickly test something" annnnnd there's an update that needs downloading, the fastest internet available to my house is stuck in the '90s. Anyway, the NEWS is never updated and I never find anyone else talking about it. So. . . how about: What's New this time?
We had to release a small hotfix that adds a warning to the launcher for users with the buggy nvidia driver.
I would suggest watching the update speculation thread as there you will find people discussing the latest teasers and devs/mods (or community memeber) usually give you a sense of what that 300MB update is. https://www.beamng.com/threads/update-speculation-thread.20246/page-776#post-1018044