Paid to Subscription - is my code / understanding correct?

New iOS and RevenueCat developer here, and I’m converting a paid app to subscription. I’ve read this article, and gone through the PurchasesHelper code.

To help me understand better, and so it’s easier for me to maintain later on, I prefer not to simply copy and paste code. So I’ve done my best to write this my self.

Since it’s difficult to test properly in a sandbox environment (or is beyond my technical know-how) and the importance of getting this right on the first try, I was wondering if someone can take a look at my code below and let me know if this will work in production:

In my app struct, I have:

@main
struct MyApp: App {

    init() {
        Purchases.logLevel = .error
        Purchases.configure(
            with: Configuration.Builder(withAPIKey: AppConstants.apiKey)
                .with(storeKitVersion: .storeKit2)
                .build()
        )

        Purchases.shared.delegate = PurchasesDelegateHandler.shared
    }


    var body: some Scene {
        WindowGroup {
            ContentView()
                .task {
                    do {
                        // Fetch the available offerings
                        UserViewModel.shared.offerings = try await Purchases.shared.offerings()
                    } catch {
                        print("Error fetching offerings: \(error)")
                    }
                }
        }
    }
}

and the UserViewModel:

/* Static shared model for UserView */
class UserViewModel: ObservableObject {

    static let shared = UserViewModel()

    /* The latest CustomerInfo from RevenueCat. Updated by PurchasesDelegate whenever the Purchases SDK updates the cache */
    @Published var customerInfo: CustomerInfo? {
        didSet {

            // Purchased before build 6? Automatic entitlement to full app

            if let originalApplicationVersion = customerInfo?.originalApplicationVersion {
                if AppConstants.backwardsCompatibilityVersions.contains(originalApplicationVersion) {
                    subscriptionActive = true
                    return
                }
            }

            // Otherwise, get current entitlement

            subscriptionActive = customerInfo?.entitlements[AppConstants.entitlementID]?.isActive == true

            print(customerInfo?.originalApplicationVersion)
        }
    }

    /* The latest offerings - fetched from MagicWeatherApp.swift on app launch */
    @Published var offerings: Offerings? = nil

    /* Set from the didSet method of customerInfo above, based on the entitlement set in Constants.swift */
    @Published var subscriptionActive: Bool = false {
        didSet {
            subscriptionNotActive = !subscriptionActive
        }
    }

    @Published var subscriptionNotActive: Bool = true
}

Is this sufficient? There will be a “Restore Purchases” button at the bottom of the PaywallView. If I’ve understood the PurchasesHelper GitHub documentation, a call to Purchases.shared.restorePurchases() is enough, and there is no need to call syncPurchases().

Is my understanding of restorePurchases() vs syncPurchases() correct?

Thank you!