# Hanna — Orchestration Log

**Timestamp:** 2026-03-21T06:14:44Z  
**Session:** Stability Bug Investigation Planning  
**Role:** COM Interop Expert

## Work Performed

- Reviewed COM API call sequences in session/batch code paths under timeout conditions
- Analyzed cleanup and resource release patterns across ExcelBatch, ExcelSession, and ExcelShutdownService
- Identified observable COM state signals that indicate timeout behavior, recovery success, and cleanup correctness
- Validated connection and query table refresh semantics for stability under serial operations

## Findings

**Session/batch architecture:**  
COM cleanup uses try-finally with exponentiated backoff retry on Quit failures. Timeout is currently 30 seconds with 6-attempt retry for transient COM busy states.

**Observable signals (highest confidence):**
- `QueryTable.Refresh(false)` behavior under session timeout (data load vs. state corruption)
- `ExcelApp.Quit()` success/failure rate and timing after forced timeout
- ComUtilities.Release() call correctness in finally blocks (verifiable via leak audit)
- PID tracking and process cleanup on session crash

**Risk areas:**
- Nested QueryTable refresh calls during active Power Query operations
- Cross-session workbook reopen after timeout without full GC cycle
- Modal dialog or user prompt blocking Quit on timeout

## Output

- Observable test signals ranked by confidence and ease of detection
- Session/batch code paths flagged for cleanup audit
- QueryTable and Quit timeout behavior recommendations for regression test design

## Team Updates

- Confirmed COM API boundaries for serial workflow testing
- Validated cleanup patterns support regression-first discipline
- Identified specific COM call sequences for targeted test coverage
