jailbreak for ad removal?

i caved and upgraded my kindle. i was able to chat with costumer service to remove the ads for free with the previous model but that’s not an option anymore. I’ve been seeing more stuff about jailbreaking and i’m curious but is it permanent? i really just want the ads gone and not give amazon more money even if it is $20… i do have KU for free right now and don’t know if it will go away if i do jailbreak.

If i cant jailbreak just for ad removal and go back to how the kindle set up was before does anyone have an alternative way of removing ads at home for free with a computer? TIA