2019 has already seen evidence that the SHIELD TV may be getting a new refresh - with the new Tegra X1 processor - soon. Now, a new FCC filing points to a wholly new device with this branding. This putative device has its own code-name and references in NVIDIA's own code and scripts.
https://www.notebookcheck.net/A-completely-new-NVIDIA-SHIELD-TV-product-may-be-in-the-works-after-all.428792.0.html