On Lollipop, the process you want to disable is called "Motorola Update Services." On your phone's app settings, 'Disable' is probably greyed out. So ... download and install a free app called SD Maid. In SD Maid, go into Settings.. AppControl... and check the box that says "Include System-Apps." Now, get out of 'Settings' and go into SD Maid's AppControl section and scroll down or search til you find Motorola Update Services (system name: com.motorola.ccc.ota). Click on it and choose "Freeze app." Save and exit.
You will now see on your phone's Settings... Apps.. that the Update service is listed under "Disabled."
I installed SD Maid (full paid version), but I do NOT see: Motorola Update Services (system name: com.motorola.ccc.ota). Click on it and choose "Freeze app." Save and exit.
There is NOT any "Freeze" option. I was able to disable one of the Update apps in Settings on my Note 4 (there are two Update apps in the Settings), but I still keep getting the Update Notice, and now I cannot choose Postpone, because it's "Grey."
I called Samsung Tech Support and they told me there is no way to stop the Marshmallow Update. This is very frustrating .... I just got a second Note 4 replacement because Marshmallow killed my battery life on my Note 4. Now I'm back to Lollipop, and my battery life is better, but even Lollipop has a battery drain bug, although not as bad as Marshmallow.
Is SD Maid the only option to try and kill the Updates (without Rooting). I do not want to Root. If I had rooted my Note 4, I would not have been able to get a replacement, and also Best Buy would not do the Software Reflash (which did NOT help, but actually made the Marshmallow battery drain even worse !!!)