## ADDED Requirements

### Requirement: RC1 default branch behavior SHALL remain unchanged
Adding shadow followthrough research SHALL NOT change RC1 default branch behavior.

#### Scenario: RC1 default branch regression check
- **WHEN** RC1 default branch is replayed on current local baseline dataset
- **THEN** baseline core event/trade hashes remain unchanged

### Requirement: Probe branch SHALL be isolated from default governance path
The followthrough probe branch SHALL be available for observation but SHALL NOT become default governance path.

#### Scenario: Daily pipeline branch registration
- **WHEN** daily pipeline builds branch runs
- **THEN** probe branch appears in branch status outputs
- **AND** default branch remains `alpha_first_glued_refined_hot_cap`
- **AND** control branch logic remains `alpha_first_selective_veto`

### Requirement: Probe branch SHALL use conservative subtype scope by default
Probe branch default config SHALL only enable pending queue for `mid_zone_very_weak_b1`.

#### Scenario: Probe config defaults
- **WHEN** `alpha_first_glued_followthrough_probe_config()` is loaded
- **THEN** `glued_followthrough_pending_enabled=True`
- **AND** `glued_followthrough_allow_mid_zone_very_weak_b1=True`
- **AND** `glued_followthrough_allow_high_zone_weak_b1=False`
- **AND** `glued_followthrough_allow_ql_rebound_weak_followthrough=False`