docs(spec): 2021/22 school-level KS2 is a permanent DfE source gap, not a pipeline task

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0146VHeLAWjDVE2B5uU67jCB

docs/superpowers/specs/2026-07-11-compare-screen-redesign-design.md

@@ -252,12 +252,18 @@ mockups on 2026-07-12. The following are binding requirements for
 implementation, beyond what the mockups can show:
 
 1. **Chart truthfulness:** KS2 tests were cancelled 2019/20–2020/21
-   only; 2021/22 results exist and must be loaded (school-level rows
-   and the 2015/16 national figure, 53%, are currently missing from
-   our dataset — pipeline task). Load official England averages for
-   GPS/science expected % and the scaled scores (reading/maths/GPS) —
-   the mockups' scaled-score ticks are indicative until then. Never
-   render missing years as if time were continuous.
+   only. **2021/22 school-level figures are a permanent source gap** —
+   DfE stated it would not publish KS2 2021/22 in performance tables
+   (verified 2026-07-12 against EES, the CSP download service, and
+   DfE release notes; see `# TASK 6 VERIFICATION` in
+   `pipeline/scripts/diagnose_compare_gaps.py`). The chart's England-
+   only 2021/22 point with broken school lines is therefore the
+   correct permanent rendering; copy should say "DfE didn't publish
+   school-level figures for 2021/22", not "not in our dataset yet".
+   The 2015/16 national figure and the GPS/science/scaled-score
+   England averages ARE loadable (mapping already correct; refreshed
+   raw extract backfills them). Never render missing years as if time
+   were continuous.
 2. **Report-card summaries** count graded areas only — safeguarding is
    a separate binary flag, never included in rating counts.
 3. **Admissions:** use the real preference-breakdown fields from