Thanks Swonder, you have picked up on one or two inconsistencies.
The milestone awards and flight benefits page reads "sent via regular mail ... by the end of October," however the welcome package page reads "receive your welcome package by the end of October." I have been assured the packages were sent by October 31 - hopefully the keen ones can hold on a few more days. I'll note this inconsistency with the team.
And you're right on the second point, too. It's only boxes two and three that need ticked.
On your third point I was trying to clarify the intent of the packages and how they fit within the program, but obviously failed. They are called welcome packages, yes, but they're not a traditional welcome package that is mailed when you reach a new tier level as occurs in some other reward programs.
This offer is a short-term promotion, sent to all who are Gold members at roughly the same time, or who acquire Gold status within a set period. This is why you're receiving this offer 11 months since you became a Gold tier member.
Hope this helps to clarify. Let me know if you've got any other questions.
Darren