[General]

I'm guessing it's about time the Envision got an update since it was sold for the 2016 model year. GM Authority saw the order guide and listed a few new features we should see in the 2019 model year Envision.

The Premium trim levels will get a new GM 9-speed transmission with the other trims still equipped with the 6-speed transmission.
Midnight Amethyst Metallic color will be replaced with Satin Steel Gray Metallic.
Rear will get LED tail-lamps and the Premium trim levels will have Bi-LED headlamps.
The base, Preferred , and Essence trim levels get projector beam HID headlamps as standard

And there's more listed here: 2019 Buick Envision Gets LED Lights, 9-Speed Auto & More | GM Authority

 

[NormT]

That is great news on the HID basically on every trim level and not just Premium l and ll. That is where the NHSTA said the Envision suffered with the halogen lighting.