session · operate & reflect

Model update session

30 minutes. Held the same hour as the retro. Four mechanical moves: close witnessed assumptions, add new ones, link the signal reading to the brief, sharpen open questions. The session that compounds learning — and the one most teams skip.

When

Immediately after the Retrospective — same hour, before the room loses momentum.
If skipped today, scheduled within 48 hours. Past that, the model update doesn't happen — and if the model update doesn't happen, the learning didn't happen.

Who

PO — primary; holds the artefacts.
(Optional) Tech Lead if the cycle surfaced architectural assumptions that need updating in technical artefacts.
(Optional) Designer if a design-system assumption shifted.

Time-box

30 minutes. Mechanical work, not creative — open the Initiative Brief and Feature Brief side-by-side and make the four moves.

Inputs

The signal reading.
The retrospective output.
The Initiative Brief.
The Feature Brief.
The "What we have NOT yet witnessed" sections of both briefs.

Agenda

Time	What
0–10 min	Move 1: Close the assumptions witnessed. Open the brief's "Not witnessed" section. For each item that this cycle witnessed: mark closed, with evidence and date.
10–18 min	Move 2: Add new assumptions. What did this cycle surface that we hadn't considered? Add them with status (observed / not yet observed) and implication.
18–22 min	Move 3: Append the signal reading. Add a link from the brief's prediction section to the signal reading. The brief is now complete: problem, solution, whether the solution worked.
22–28 min	Move 4: Sharpen open questions. Strike answered ones; rewrite refined ones; add newly surfaced ones. The set of open questions is now the next discovery's agenda.
28–30 min	(If retro found a template/checklist gap) — open the template, make the change, file the PR. The retro change becomes a chain-artifact change in real time.

Outputs

Updated Initiative Brief — assumptions closed/added, questions sharpened — committed.
Updated Feature Brief — signal reading linked — committed.
(If applicable) template or checklist change committed.
A short model-update record (template) — the change log of what moved this cycle.

What good looks like

The work is small. Each move takes minutes. Together, over cycles, they are why a year-old team writes briefs a six-month-old team couldn't — because every cycle's learning is alive in the artefacts the next cycle starts from.

The test for whether the model update happened: does the next brief change because of what this cycle revealed? If yes, the update worked. If no, the update was wiki-shaped, not chain-shaped.

Anti-pattern

The session feels redundant after the retro and gets skipped. The retro produced learning; people nod; nobody writes it down where the next cycle will see it; three weeks later the next cycle begins with the same misunderstandings. Fix: the model update is mechanical, not insightful — it's the act of writing the insight down where it survives the conversation. Skipping it is skipping the only step that compounds.

A second anti-pattern: the update becomes a wiki entry, not an artefact change. A new Confluence page; a fresh Notion doc; a Slack thread with the learnings. None of these are in the path the next cycle reads. Fix: edit the brief. In place. Versioned. The next cycle reads the brief, not the wiki.

A third: no owner. Everyone assumes someone else does the update; nobody does. Fix: the PO owns it. Explicitly. Calendar-locked.

Model update session ​

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