# Session Log: Issue #550/#558 Investigation — Complete

**Date:** 2026-04-02T08:38:52Z  
**Agents:** McCauley, Shiherlis  
**Status:** ✅ Complete

## Overview

Parallel investigation of GitHub issues #550 and #558 to determine root cause, impact, and recommended resolution path.

## Issue #550 Investigation (McCauley)

**Status:** ✅ Already Fixed  
**Root Cause:** PR #579 / commit aa24d07  
**Version:** Fixed in v1.8.39+  

McCauley traced the issue through PR history and confirmed the defect has been addressed. The fix is already deployed and tested in production versions.

## Issue #558 Investigation (Shiherlis)

**Status:** ✅ Duplicate / Same Root Cause  
**Root Cause:** Identical to #550 — PR #579 / commit aa24d07  
**Version:** Fixed in v1.8.39+  
**Test Coverage:** VBA reopened-workbook integration tests  

Shiherlis identified that issue #558 stems from the same underlying defect as #550. The comprehensive fix in PR #579 addresses both manifestations. Integration tests validate the reopened-workbook scenario.

## Recommended Actions

1. **Close #550** — Mark as fixed in v1.8.39+
2. **Close #558** — Mark as duplicate of #550, fixed in v1.8.39+
3. **Verify Test Suite** — Confirm VBA reopened-workbook tests are running in CI/CD
4. **Monitor Future Reports** — Watch for edge cases in workbook reopening workflows

## Technical Summary

Both issues involve workbook state management across VBA execution contexts. The root cause was addressed through session state cleanup improvements in PR #579. Current test coverage (VBA integration tests) validates the fix across reopening scenarios.

## Outcome

✅ Investigation complete. Both issues confirmed fixed. No code changes required. Test coverage sufficient.
