Gmail – Problem with filtering and archiving Gmail

I like to archive my gmail, i.e. get it out of my inbox, once a year. I like it to be available with labels according to year, for example, all the mail that was in my inbox during the last 12 months should now be in a label called "2016", and all my outgoing mail that was in "sent" should now be in a label called "sent2016". In previous years, I would set this up on January 1st with the following procedure — let's take what I did on January 1st, 2016, as an example:

• In the search box at the top of the gmail page, I typed
  to:me after:2015/01/01 before:2016/01/01
  and then I selected all the displayed messages, and then clicked on the link that came up offering to select all such messages. Then I gave them a new label, "2015". It took a long time because there were several thousand.

  Once that was done, I would highlight everything with that "2015" label and hit the "archive" button. I figured that would get them out of my inbox.

  I don't remember what I did about messages that had been automatically filtered out due to various filters I have which label incoming messages according to the sender, recipient or subject, with the name of the listserv, for example "parents". Note, all of this type of message was supposed to bypass the inbox. (I didn't want them to have the label "2015", and somehow I achieved that.)

Twelve months ago, I had the idea to do it slightly differently this time. I set up a filter a year ago that was supposed to assign the label "2016" to all incoming mail, not bypass the inbox, and not work retroactively. My idea was that on 1/1/17, I would just edit the filter and start applying a new label, "2017" to all incoming messages, instead of "2016".

Something isn't working according to plan. The messages that were going to the inbox AND to another label, such as "PersonA", for some reason did not get labeled with "2016" throughout the year. I'm talking about filters that did not bypass the inbox.

My questions:

1. What went wrong?

2. Is there an easy fix to identify the "PersonA" labeled messages (there are a lot of different labels of this type) and not the "parents" labeled messages (there are a lot of different ones of this type as well), so as to assign the "2016" label?

3. How should I prepare for the big archiving to come 12 months from now?

Note: I usually read my email and compose messages with Thunderbird (IMAP). In Thunderbird, each "label" (in gmail) becomes a "folder" in Thunderbird.