Compilation error with Xcode 26 beta 1

I am trying to build my app with Xcode 26 beta 1. RevenueCat is generating errors:

For many functions, I’m getting this error.

“Concurrency is only available in iOS 13.0.0 or newer”

Here is an example of the code in Obsoletions.

    func paymentDiscount(for discount: SKProductDiscount,

                         product: SKProduct) async throws -> SKPaymentDiscount {

        fatalError()

    }

I am using RevenueCat 4.43.3

Is there a way I can avoid these errors - I am not ready to move to RC 5.x yet.

My code supports iOS 16 or later.