Question [Q] No KitKat on my One Max?

I've just bought a brand-new HTC One Max (international model, unlocked) and it seems that there is no Android 4.4.2 update, it just says that current version - 4.3 - is the newest version.

How do I update my phone without voiding warranty?
Samsung Galaxy S
Semaphore Kernel

Samsung Galaxy SIII
CyanogenMod 11

HTC One Max
Stock untill I get bored