AWS Elastic Beanstalk

Hello Everyone, I don’t know this is right place to ask AWS based query. I am learning AWS and My few interviews are scheduled next to next week on skype. Can anyone explain how does the AWS Elastic Beanstalk apply updates? As my research AWS Elastic Beanstalk readies a duplicate copy of the instance. Thereafter, it routes the traffic to the duplicate instance so as to avoid a scenario where the update application fails, this is according to AWS interview questions post when I was searching for this query. Can anyone know this is the perfect description of AWS Elastic Beanstalk?

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