The Moto E4 Plus is one of the many, many, many phones that Motorola has released this year. Its main selling point is the massive 5,000mAh battery, giving you 2+ days of intensive use on a single charge (I would kill for a Pixel with that). David mostly praised the phone in his review, but as with all Motorola devices, slow or non-existent updates is a given.
It has taken a few months, but Motorola has released the kernel source code for the Moto E4 Plus. The source code for the normal Moto E4 was released in September. There are actually three different pushes for the E4 Plus, presumably covering the different variants sold worldwide.
The code makes it easier for custom ROMs to be developed for the phone, so perhaps we'll see more mainstream ROMs support the phone soon. Developers can find the code at the source links below.