Taxcycle release naming convention - pls clarify

I like to keep track of the Taxcyle release numbers and dates with the release notes to help me understand and organize the new features, fixes, and best practices.

Right now I am putting T1 2018 to bed and documenting my learnings and self recommendations to improved my workflows and checklists for T1 2019.

While reviewing the 2018 release notes I have noticed the following:

FIRST NUMBER = T1 YEAR
I notice that you use the T1 tax year for the first number.
Currently this is 8.

SECOND NUMBER VARIES - 0, 1, 2

I notice that pre-tax season the second number is 0. This seemed to have started sometime in October.
8.0

The first such release that I had downloaded was
TaxCycle version 8.0.33980.0—Microsoft .NET Framework 4.7.2 and TaxCycle Forms 2018, 2018-10-25.

On or about the start of tax season the second number becomes 1.
8.1

As of the release on 2019-06-27 the second number became 2.
8.2

TaxCycle version 8.2.35573.0 - 2019-06-27

TaxCycle version 8.2.35608.0—2019-07-05

Q1 - What does the numeral 2 signify?

Q2 - Which is the best URL on which to find all the release notes for a given year?

THESE ARE MY NOTED LINKS

Search on tag = release+notes

TaxCycle 2019 - Latest Current Download and Major Prior Versions - 2012 to 2017
https://www.taxcycle.com/Support/Download

How to config auto updates
https://www.taxcycle.com/Support/Auto-update-files