The lifetime warranty is valid and for all knives.
If for any reason something happens to the knife, as used properly, it will be repaired or replaced free of charge (however, the required freight rates apply).
The purpose of the knife is only and only to be a cutting tool, and nothing else, if subjected to misuse / abuse, loses the guarantee.
That is, the warranty does not cover damages that may be caused by misuse, abuse of the knife or problems caused by its user.
Examples of misuse of a knife are to use it as a hammer, as an axe, as a can opener, as a lever, as a tool to pry nails, hammer on its back or handle, twist the blade sideways or other not normal use as a cutting tool.
The materials used in the manufacture are of quality, however, it is convenient to have the notion that nothing lasts forever. Especially natural materials are subject to the natural action of time and can contract and expand, suffer cracks, lose part of the original finish or even suffer changes in color and texture, especially if not properly cared for.
As a rule these changes are only aesthetic, and do not generally affect the quality and performance of the knife.
My handmade knives will accompany you for many years, probably for a few generations, but your life will be longer, the more careful you are to maintain the knife.