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This document defines the Time Zone Information Format (TZif) for representing and exchanging time zone information. The typical application is iCalendar or scheduling system.

This document is ready, and I only found a few nits in it.
1.Section 3, what is 32-bit transitions, what is 64 bit transitions, how it is different from 32-bit transition times and leap second occurrences, why header should also include 32 bit transitions? Wouldn’t header a 44-octet header? Would it be great to add transition as a new term in the terminology section.

2.Section 3.2 What is the header of the 64-bit data block, how it is different from 64bit transitions? Isn’t header of the 64 bit data block 44-octet header? 

3.Leap second records definition
How 64 bit data block can be used to accommodate 16 octet records?
4. Can you explain footer is needed for version 2 and 3 of TZif file while not needed for version 1?