> If you dig into the time routines that use tzdata, you see they must use an unstable conversion process that _may_ converge, but has a simple counter protect

> If you dig into the time routines that use tzdata, you see they must use an unstable conversion process that _may_ converge, but has a simple counter protecting it in the case that it _does not_ converge and in that case it just gives you a best guess time that may still be wrong anyways. What does this mean? Can you explain in a little more detail, or link to somewhere I might read about this? I haven't used tzdata myself, but I understand it in broad strokes as a list of time zones, and a list of which offsets apply to which timezones at which given dates. What am I missing?