How many days until a monthly subscription is renewed?

Hi, sorry for the delay. Here is an example webhook of a purchase made on May 31st and you can look at the expiration_at_ms and see that it is set to renew on June 30th:

{
  "api_version": "1.0",
  "event": {
    "app_id": "app1234567890",
    "app_user_id": "app_user_id",
    "commission_percentage": 0.15,
    "country_code": "USA",
    "currency": "USD",
    "entitlement_id": null,
    "entitlement_ids": [
      "premium"
    ],
    "environment": "PRODUCTION",
    "event_timestamp_ms": 1717146353139,
    "expiration_at_ms": 1719738341000,
    "id": "12345678-1234-5678-1234-12345678901",
    "is_family_share": false,
    "offer_code": null,
    "original_app_user_id": "app_user_id",
    "original_transaction_id": "123456789012345",
    "period_type": "NORMAL",
    "presented_offering_id": null,
    "price": 9.99,
    "price_in_purchased_currency": 9.99,
    "product_id": "monthly",
    "purchased_at_ms": 1717146341000,
    "store": "APP_STORE",
    "subscriber_attributes": {
      "$attConsentStatus": {
        "updated_at_ms": 1717146351844,
        "value": "notDetermined"
      }
    },
    "takehome_percentage": 0.85,
    "tax_percentage": 0.157,
    "transaction_id": "123456789012345",
    "type": "INITIAL_PURCHASE"
  }
}