SM-J337A still on April 1, 2018 Android Security Patch Level

Hello Community,

I have a Samsung SM-J337A that is still on the April 1, 2018 Android security patch level. A few weeks ago, I chatted with an AT&T representative and she informed me that the manufacturer (Samsung) is responsible for pushing security patches and its up to them to decide when that will be. I have waited a few months and see there is a December 1, 2018 release that was released on January 8, 2019 as per below blink:

https://www.att.com/devicehowto/tutorial.html#!/stepbystep/id/stepbystep_KM1268250?make=Samsung&model=GalaxyJ32018&gsi=02wyll

Software update for the Samsung Galaxy J3 (2018) (J337A)
Release date: January 8, 2019
Android version: 8.0.0
Security patch level (SPL): December 1, 2018
Baseband version: J337AUCU4ARL1
Build number: R16NW.J337AUCU4ARL1
Previous version: J337AUCU3ARJ1
File size: 120.7MB

In another month from now, it will be a year since my phone received a patch update, so I decided to chat with an AT&T representative again. This time the representative said she can request the manufacturer (Samsung) to push out the update and that I will receive it within 24 hours. I thought this was odd because updates should be automatic, why should I have to chat to a representative for them to push an update to me. She responded by saying that she put in the request for the updates be pushed out automatically when they are available. This still didn't answer my question, does this mean that every SM-J337A user on the April 1, 2018 security patch level has to notify AT&T for them to put in a request for them to receive updates automatically?

Nevertheless, I waited 24 hours and clicked "Check for updates" and received "Current software is up to date." My security patch level is still April 1, 2018.

Does anyone actually know what is going on with SM-J337A's that are on the April 1, 2018 security patch level? Is AT&T or the manufacturer responsible for pushing the updates? How will the user know it has the latest update?

Thanks in advance!