Transactions for many auto-renewal subscription products

We are currently testing the restoration of auto-renewal subscription products (1 month) in a sandbox environment.

Restoration is implemented by executing

restoreCompletedTransaction () .

However, when a transaction is restored, it also includes items that have expired in the past, and depending on the status of contract renewal, nearly 100 transactions will be returned.

So, finishTransaction() is called for nearly 100 transactions, but it takes an enormous amount of time for all transactions to be deleted.

Until the transaction disappears, even if you make a purchase processing request, you will have to wait, which will make users feel very uncomfortable.

So I have a question.

Is there a limit to the number of transactions that can be restored?

Will expired products remain forever?
Or will it disappear in a month or half a year?

If the more I update, the more transactions I have, I have to call the finishTransaction() every time I restore, is that okay?