Warranty Question

A few weeks ago my phone was dropped while cleaning out the weird gunk that build up in the case and the back glass got cracked. I can live with that, but my phone just turned off and won't turn on if not plugged in. This isn't my first replacement and usually when I have an issue, I just call in and they send a new one free but will it be different this time? Am I doomed to pay the 5 ? Much obliged for the assist in advanced.

What's samsung's warranty process like?

Since tripping KNOX is a real concern, is the warranty worth it, do they send you a package and have someone schedule a delivery, or is it ****ty making you pay for shipping/extra costs each way over weeks? Any experiences?

Reverting back to stock for Warranty Purposes

Need to send back my Z3 compact for some warranty issues.
What is the best way for me to revert to stock?
I already have all my apps backed up and a twrp backup as well.

I am rocking a modified rom, and want to make sure I don't meet problems due to it. My bootloader is not unlocked.
Also I ordered my phone from the UK from Handcent Is there a specific firmware I should use then?
What do i need to do to revert back to complete stock?

Thanks for any help!

KNOX and warranty

Do you think that Samsung will always void a warranty if KNOX counter is set to void? What if the screen isn't working, or if the phone stops charging, or if the battery is defective? How would that policy hold up in court? Samsung acts reasonably, right?