我正在通过Google Developer Subscription Purchase的响应中的以下链接查看此文档：
https://developers.google.com/android-publisher/api-ref/purchases/subscriptions#methods
具体来说，对于字段linkedPurchaseToken，提到了两种情况：
- 重新注册已取消但未失效的订阅
- 从先前的订阅升级/降级
我不确定情况＃1何时发生。尝试购买，取消和还原（虽然没有失效）自动续订的订阅，但是还原后，我在响应中没有得到linkedPurchaseToken。
以下是三种情况下的答复：
购买后：
{
"kind": "androidpublisher#subscriptionPurchase","startTimeMillis": "1573546099994","expiryTimeMillis": "1573548136296","autoRenewing": true,"priceCurrencyCode": "INR","priceAmountmicros": "85000000","countryCode": "IN","developerPayload": "","paymentState": 1,"orderId": "GPA.3359-7048-7648-05268","purchaseType": 0,"acknowledgementState": 1
}
取消后：
{
"kind": "androidpublisher#subscriptionPurchase","expiryTimeMillis": "1573548016296","autoRenewing": false,"cancelReason": 0,"userCancellationTimeMillis": "1573546553870","cancelSurveyResult": {
"cancelSurveyReason": 0
},"acknowledgementState": 1
}
还原后：
{
"kind": "androidpublisher#subscriptionPurchase","acknowledgementState": 1
}
在什么情况下应该为＃1情景获取LinkedPurchaseToken吗？