cables warranty

I agree with the previous poster about contacting Apple Support directly: https://getsupport.apple.com/

I can add a little more information, or context, about exchanging cables in an Apple Store, though. Most likely if someone received a free replacement, the cable worked with a device that was still covered by an AppleCare warranty.

Personal example:

While different devices were still covered under their original 2-year AppleCare+ warranties, I was able to exchange damaged lightning cables for free replacements. I first contacted Apple Support to see if it was possible under my warranty. Then, I had to make an appointment at the GeniusBar of my local Apple Store.

The store employees verified my warranty status, but it was a quick and easy process from there. I gave the damaged cable to the Apple employee and received another lightning cable. They made sure the replacement worked before I left.

Once the warranty expired, I (the owner) was responsible for buying a replacement cable, if needed.

Cables for what device? I have never heard that rumor and I've been in these forums for nearly 20 years.

You probably want to ask Apple because everyone responding here is an end-user like you, not an Apple employee. No answer here is considered "official."