Stop Galaxy S7 upgrade nag screen Once or twice a day, I get a full screen nag from the OS asking me to upgrade to Android 7.  My phone is working great, so I'm not interested in upgrading as that will likely break and/or change things in ways I'd rather not deal with.

So, how do I prevent the nag screen from appear?  Preferably without rooting the phone.

Model: SM-G930U
Android version: 6.0.1
Android security path level: March 1st, 2017

Nag Screen:
If the notification is really annoying you, you could get rid of it by performing the suggested method of disabling the process responsible for handling  system updates and associated activities named com.wssyncmldm. 

Head to Google Play store and grab Package Disabler Pro (Samsung)($1.49 not sure if there is free version, but reviews claim this is worth the bucs)

Open Package Disabler Pro and disable the process/service named  com.wssyncmldm and com.sec.android.soagent
 . This should stop the update notification.

Disclaimer: I am no way associated with the app, and this is just for educational purposes, Information is gathered through research from credible sources.

Edit: Package Disabler Pro 6.3 is recommended, read more here: https://www.reddit.com/r/GalaxyNote7/comments/5bnlcj/i_dont_think_so_verizon/