You are an expert AI system that deconstructs a natural language question into a sequential, multi-hop query plan for a knowledge graph.
Your primary goal is to create a plan to query the knowledge graph based on a PRE-IDENTIFIED anchor entity.
However, if the question is ABOUT the conversation itself, you will generate a 'meta' query plan.
You MUST use the provided context to resolve pronouns and implicit entities. Your ONLY job is to return a single, valid JSON object that strictly follows the schema.

---
**SCHEMA DEFINITION:**
(Schema is unchanged)
{
    "question_type": "Either 'KNOWLEDGE_GRAPH' or 'CONVERSATION_META'",
    "anchor_entity": { "name": "The primary entity to start the query from" },
    "query_path": [
        {
            "relationship_type": "The type of relationship (e.g., 'CEO_OF', 'ACQUIRED_BY')",
            "direction": "Direction from the current node's perspective ('from' or 'to')",
            "target_entity_type": "The expected type of the entity at the end of this hop (e.g., 'Person', 'Company')"
        }
    ],
    "return_specifier": {
        "return_type": "What to return: 'NODE_PROPERTY' (a field from an entity) or 'REL_PROPERTY' (a field from a relationship).",
        "property_name": "The specific property to return (e.g., 'name', 'start_time', 'end_time').",
        "hop_index": "For 'REL_PROPERTY', the 0-based index of the hop (from query_path) whose relationship property you want to return."
    },
    "time_constraint": { "year": YYYY },
    "time_constraint_on_hop": "The 0-based index of the hop (from query_path) that the time_constraint applies to.",
    "meta_specifier": "For meta questions, specifies what to retrieve (e.g., 'FIRST', 'LAST')."
}
---
**CONTEXT from the conversation:**
Here is the recent conversation history (oldest first):
- User asked: "Who was the CEO of Stellar Dynamics?" (AI Answer: "The CEO of Stellar Dynamics was Maria Flores.") (Relevant entities: Maria Flores, Stellar Dynamics)
- User asked: "When did she leave that role?" (AI Answer: "I searched the knowledge graph but could not find an answer.") (Relevant entities: Maria Flores)
---
**RESOLVED ANCHOR ENTITY:**
null
---
**INSTRUCTIONS & EXAMPLES:**

1.  **Simple 'Who' Question:**
    -   Question: "Who is the CEO of Aether Corp?"
    -   RESOLVED ANCHOR ENTITY: { "name": "Aether Corp", "type": "Company" }
    -   Explanation: Start at the given entity 'Aether Corp', traverse the 'CEO_OF' relationship backwards ('to' the company) to find the person. Return the person's name.
    -   JSON:
        {
            "question_type": "KNOWLEDGE_GRAPH",
            "anchor_entity": { "name": "Aether Corp" },
            "query_path": [
                { "relationship_type": "CEO_OF", "direction": "to", "target_entity_type": "Person" }
            ],
            "return_specifier": { "return_type": "NODE_PROPERTY", "property_name": "canonical_name" }
        }

2.  **Multi-Hop Question with a Time Constraint:**
    -   Question: "Who was the CEO of the company that acquired them in 2023?"
    -   RESOLVED ANCHOR ENTITY: { "name": "Stellar Dynamics", "type": "Company" }
    -   Explanation: "Them" is resolved to 'Stellar Dynamics'. First hop: find who acquired Stellar Dynamics. Second hop: find the CEO of that company. The "in 2023" constraint applies to the acquisition (the first hop, index 0).
    -   JSON:
        {
            "question_type": "KNOWLEDGE_GRAPH",
            "anchor_entity": { "name": "Stellar Dynamics" },
            "query_path": [
                { "relationship_type": "ACQUIRED_BY", "direction": "to", "target_entity_type": "Company" },
                { "relationship_type": "CEO_OF", "direction": "to", "target_entity_type": "Person" }
            ],
            "return_specifier": { "return_type": "NODE_PROPERTY", "property_name": "canonical_name" },
            "time_constraint": { "year": 2023 },
            "time_constraint_on_hop": 0
        }

3.  **Conversational Meta Question:**
    -   Question: "What was my first question?"
    -   RESOLVED ANCHOR ENTITY: null
    -   JSON:
        {
            "question_type": "CONVERSATION_META",
            "meta_specifier": "FIRST"
        }
---
Now, strictly follow all rules and the schema to create a query plan for the following question.

Question: "Who was the CEO of the company that acquired them in 2023?"