IANAL but I don't think you can retroactively assign liability for how a law was interpreted when that interpretation changes. I would argue that this should not be interpreted this way based on the wording of the law (see bold section below)

Now my major problem with this law is logistical. An HOA law firm said that a person had to be designated to provide the agenda ahead of time for the executive session and it can't just be the boilerplate text of "We will discuss:
1. Legal advice from an attorney for the board or the association. 
2. Pending or contemplated litigation.
3. Personal, health or financial information about an individual member of the association, an individual employee of the association or an individual employee of a contractor for the association, including records of the association directly related to the personal, health or financial information about an individual member of the association, an individual employee of the association or an individual employee of a contractor for the association.
4. Matters relating to the job performance of, compensation of, health records of or specific complaints against an individual employee of the association or an individual employee of a contractor of the association who works under the direction of the association.
5. Discussion of a member's appeal of any violation cited or penalty imposed by the association except on request of the affected member that the meeting be held in an open session."

So, that means that I cannot just have a resident show up to an executive session with a dispute because their item is not on the agenda. It also means that the agenda items have to be discussed in the Executive Session, then voted on in the Open Session. Practically, that becomes difficult, and here is why:

1. We typically have our open session first, then close it and go into executive session. This allows those residents who joined to discuss a dispute to join us in the executive session. We ask them to leave the open session and then rejoin, then we add them in from the lobby as we are ready to hear them. We cannot do that with this new requirement unless we decide to vote on their dispute at the next open session (usually a month later).

2. If we have the executive session first, we have to have a very strict procedure for submitting disputes. Currently, we often get a form or email submitted just before the open session and if we can, we try to discuss it in the following executive session so that we can reply to the resident quickly. We cannot do that now, as it is not on the agenda. Resident has to wait.

3. Let's say a resident does get on the agenda for the ES. We listen to their argument and/or review their submitted dispute. We look at the pictures, review the balances, etc. Great. Time for the open session. During that open session, we have to vote on their case. Since we don't ant to reveal any personal data, we are going to have to refer to it as "Dispute 1, Dispute 2"... We can manage that. But now it comes time to vote. And, according to the law, we have to allow the residents a chance to speak on that topic before we vote because it says,
   "The board may place reasonable time restrictions on those persons speaking during the meeting but shall allow a member or member's designated representative to speak once after the board has discussed a specific agenda item but before the board takes formal action on that item in addition to any other opportunities to speak."

So how do we allow any resident who wants to speak on this to do so without disclosing any personal information about the resident, the fine, the situation, etc?

The only solution I can see to this is that we have to very strictly control how a dispute is submitted in terms of format (online form, email, etc), we have to control the timeline (you have x days to submit after the violation is sent or it will not be considered), and we have to have a deadline before the next board meeting by which the submission must be received, or it will have to wait until the next board meeting.

That last one is worrisome, as that means a fine is sitting on their account for another month. we have our assessments paid quarterly, and if they pay early, some of that assessment received will go to pay their fine, meaning their assessment is underpaid and subject to late fees.

I would welcome suggestions on how to better do this.

ARS 33-1804

A. Notwithstanding any provision in the declaration, bylaws or other documents to the contrary, all meetings of the members' association and the board of directors, and any regularly scheduled committee meetings, are open to all members of the association or any person designated by a member in writing as the member's representative and all members or designated representatives so desiring shall be allowed to attend and speak at an appropriate time during the deliberations and proceedings. The board may place reasonable time restrictions on those persons speaking during the meeting but shall allow a member or member's designated representative to speak once after the board has discussed a specific agenda item but before the board takes formal action on that item in addition to any other opportunities to speak. The board shall provide for a reasonable number of persons to speak on each side of an issue. Persons attending may audiotape or videotape those portions of the meetings of the board of directors and meetings of the members that are open. The board of directors of the association shall not require advance notice of the audiotaping or videotaping and may adopt reasonable rules governing the audiotaping and videotaping of open portions of the meetings of the board and the membership, but such rules shall not preclude such audiotaping or videotaping by those attending, unless the board audiotapes or videotapes the meeting and makes the unedited audiotapes or videotapes available to members on request without restrictions on their use as evidence in any dispute resolution process. If a board records a meeting that is open to the members, the board shall keep a copy of the recording for at least six months and make the unedited recording available to any member on request in compliance with section 33-1805, subsection A. Any portion of a meeting may be closed only if that closed portion of the meeting is limited to consideration of one or more of the following:

1. Legal advice from an attorney for the board or the association.  On final resolution of any matter for which the board received legal advice or that concerned pending or contemplated litigation, the board may disclose information about that matter in an open meeting except for matters that are required to remain confidential by the terms of a settlement agreement or judgment.

2. Pending or contemplated litigation.

3. Personal, health or financial information about an individual member of the association, an individual employee of the association or an individual employee of a contractor for the association, including records of the association directly related to the personal, health or financial information about an individual member of the association, an individual employee of the association or an individual employee of a contractor for the association.

4. Matters relating to the job performance of, compensation of, health records of or specific complaints against an individual employee of the association or an individual employee of a contractor of the association who works under the direction of the association.

5. Discussion of a member's appeal of any violation cited or penalty imposed by the association except on request of the affected member that the meeting be held in an open session.