AWS SDK for .NET Retries and Timeouts documentation has some, though I have no idea if they’re enough.
For AWS S3, there might also be a chance that a libraries update would help. It looks like last one was 9/17. Maybe using more settings below could avoid the major runtime or process work, at least where they apply?
AmazonS3Config
HttpWebRequest Class (.NET Framework)
System.Net.HttpWebRequest: Property Members (Mono)