I want to go over why they are different. Yes, country but also carrier. I won't bore you with a link to why old phones (yes, 2 years is old) don't get updates.
There's nothing really wrong with your current OS but there are folk that want the latest and will pay for that with a new phone.
So the answer is if and when the carrier and maker decide to issue such but at 2 years the population has gone down. Here, ATT noted when users were changing out phones under 2 years about 5 years ago so the upgrade time frame is working against you.
This is why you have to decide if it's worth the risk to go off the reservation (use non-official updates.)
Hi ~ I live in Germany and I own a Samsung Galaxy J3 2016 and I can't seem to update Marshmallow.
It's already been about two months since my last update and I'm still stuck with lollipop 5.1.1. To be honest I don't even know if this update is possible on my phone. But I heard that lots of other users that use this phone already received the update. So it's quite bizarre.
On the other hand I've seen lots of other users that are suffering the same problem. I also went on other forums to see if I could get any advice or help but all the answers were different.
I either can't get the update at all because my phone is outdated and has reached it's maximum update capacity. Even though my phone is only two years old. Or only certain models or colors can get this update. I have a black model J320F. So I'm not sure about mine. Also I read that lots of people say it's depended on the country. As far as I know the J3 2016 has already received the Marshmallow update in the US. But I live in Europe and it's a bit critical here.
I also don't want to hack into my phone and reboot it. I don't want to risk it and damage my phone. Moreover I rather not buy a new phone and rather wait for the official update if it's even coming.
I hope I can get an answer soon. And thank you in beforehand! I would appreciate it very much! ~

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