What is Out-of-office handling?
Reading the return date from an auto-reply and holding the next step until then, instead of ending the sequence or sending into an empty inbox.
An out-of-office auto-reply is technically a reply, so a naive stop-on-reply ends the sequence for someone who never saw the email. The better behaviour: detect the auto-reply, parse the return date, hold every remaining step (and any open task) until that day, then continue. If no date is given, continue on schedule. A real reply from the person ends the hold.