Why is_in_billing_retry_period field appear while my subscription normal expired

I turn off the auto renwal, and after the current subscription expired, I call verifyReceipt api to check the latest status. I just found that

"pending_renewal_info": [
    {
      "auto_renew_product_id": "co.ringalarm.swtich.monthly",
      "is_in_billing_retry_period": "0",
      "product_id": "co.ringalarm.swtich.monthly",
      "original_transaction_id": "2000000333327838",
      "auto_renew_status": "0"
    }
  ],

It is odd cause I thought this field is appear while subscription is into the billing retry.

Does this field can help me to decide whether the subscription is expired?