How to rollback Samsung s6 to Android 5 after Marshmallow update?

[Sergey]

Hi there!

I just updated my s6 to the latest Android 6, and it is a buggy OS. The most annoying bug that makes me hate my own phone and everyone who guilty in the bug is: I have to do 2 additional steps each and every time I unlock my phone!

I use pattern unlock and to unlock phone, first I have to swipe, than enter pattern, than it opens 'Phone application' which i should close.

Ideally I want this bug fixed, but I understand that it takes time and will not be fixed for a long time, because this bug reported 2 years ago, (for Android 5) and still not fixed, because it has very low priority. But, I did not have this issue  before update.

So, my question is: How can I downgrade my phone back to Android 5 without loosing warranty?

Or, where I can exchange the phone for a new one, that is not updated yet?

I think, I am eligible for free exchange, because the phone is broken now and it is manufacturer's or Telus fault.

Thank you for understanding,

Sergey.

[NFtoBC]

A web search is likely the best route to learn methods to downgrade your phone to a previous version of Android. 

[Sergey]

Yeah, I know how to do it, but first of all, flashing new firmware will break warranty, and I do not want to loose it.

[Nighthawk]

Unless Samsung presents you with another option, downgrades from the device manufacturer are not common.