How to migration from Original StoreKit to StoreKit2

Hello.

I have a question about migrating from Original StoreKit to StoreKit2.

In my app, there are two in-app purchase products implemented using Original StoreKit: Product A and Product B.

For each product, there are separate backend servers, and due to certain reasons, we need to migrate one of those servers to use the AppStore Server API instead of the VerifyReceipt API.

During this migration, the iOS app needs to have code that combines both Original StoreKit and StoreKit2 for each product.

I heard that combining StoreKit2 with the VerifyReceipt API is not recommended. To avoid doing so, I believe the implementation would look like the below. Is this approach problematic? Is it not recommended by Apple?

If anyone has successfully implemented a similar migration and has insights, I would appreciate hearing about it.

Code implemented using Original StoreKit

SKPaymentQueue.default().add(payment)

    func paymentQueue(_ queue: SKPaymentQueue, updatedTransactions transactions: [SKPaymentTransaction]) {
        for transaction in transactions.filter({ $0.payment.productIdentifier.hasPrefix("...Original StoreKit product only...")}) {

            switch transaction.transactionState {
            case .purchasing: break

            case .deferred: print(Messages.deferred)

            case .purchased: handlePurchased(transaction) // send base64 encoded receipt file.
            case .failed: handleFailed(transaction)

            case .restored: handleRestored(transaction)
            
            @unknown default: fatalError(Messages.unknownPaymentTransaction)
            
            }
        }
    }

Code implemented using StoreKit2

let result: Product.PurchaseResult = try await product.purchase()

switch result {
case .success(let verification):
	let transaction = try checkVerified(verification)
	
	// send transaction id
	// ...
	
	await transaction.finish()
case .pending:
	break
case .userCancelled:
	break
@unknown default:
	break
}

func observeTransactions() -> Task<Void, Error> {
	return Task(priority: .background) {
		for await result in Transaction.unfinished {
			do {
				let transaction = try self.checkVerified(result)
				guard transaction.productID.hasPrefix("... StoreKit2 product only...") else {
					return
				}
				
				// send transaction id
				// ...
				
				await transaction.finish()
			} catch {
				// ...
			}
		}
	}
}