Keyboard replacement program - second time?

Hello,

I am about to buy a used macbook pro 2017. I know that it already went through keyboard replacement (this year). As far as I know, the keyboard gets replaced with exactly the same version. What if it breraks again? The keyboard replacement is valid for 4 years from purchase date, however, when laptop gets back from the service, you get 12 months of warranty. What if this warranty runs out, but keyboard breaks again (and 4 years from purchase date did not pass yet)? Can I get free repair/replacement again in such case?