CancellationTokenSource in using block inconsistently triggers AsyncFixer04

[evieeddins]

I'm using a CancellationTokenSource for two asynchronous actions, then awaiting them using Task.WhenAny

But this is triggering AsyncFixer (Code AsyncFixer04) in a way that I don't understand.
If I set the scope of the CancellationTokenSource with a using statement in brackets, like so

using System.Threading;
using System.Threading.Tasks;

namespace AsyncFixerIssue
{
    internal class Program
    {
        static Task Main(string[] args)
        {
            using (var cts = new CancellationTokenSource())
            {
                var a = Task.Delay(1, cts.Token);
                var b = Task.Delay(1, cts.Token);

                return Task.WhenAny(a, b);
            }
        }
    }
}

it triggers a warning from AsyncFixer04.

But if I format it like this, there's no problem

static Task Main(string[] args)
{
    using var cts = new CancellationTokenSource();
    var a = Task.Delay(1, cts.Token);
    var b = Task.Delay(1, cts.Token);

    return Task.WhenAny(a, b);
}

Also, I can just set cts.Token to a variable and make the analyzer happy

static Task Main(string[] args)
{
    using (var cts = new CancellationTokenSource())
    {
        var cancellationToken = cts.Token;
        var a = Task.Delay(1, cancellationToken);
        var b = Task.Delay(1, cancellationToken);

        return Task.WhenAny(a, b);
    }
}

It seems like either all of these should trigger the analyzer, or none of them should.
Is this a bug?
If not, what's your recommended fix for passing along a CancellationTokenSource?