Compare the following two organizational directories to identify changes:
**Before Directory:**
- Department A: John Doe, Manager
- Department B: Jane Smith, Manager
- Department C: Tom Brown, Manager
**After Directory:**
- Department A: John Doe, Director
- Department D : Jane Smith, Senior Manager
- Department C: Rachel Green, Manager
Please identify:
1. Renames, merges, or splits of departments.
2. Leadership moves.
3. Impacts on existing teams.