Soapbox Mailer uses Amazon SES's bounce mechanisms to immediately report all data provided by your recipient's email service provider. While Amazon SES does report that the type of bounce is a "soft" bounce when an out of office auto-responder is triggered by the recipient's system, Amazon SES does not provide data about the email body content of the out of office response itself.
Additionally, Amazon SES does not provide information that allows us to 100% confirm that the bounce is an out-of-office bounce versus other transitory bounces. We will continue to monitor these bounce reporting features provided by Amazon SES to ensure we can provide our organizations as much detail as possible for all bounce types.