...
Where the Overfill limit is set to, defines the maximum time that a listener can receive replaced content as Ads or Fill in excess of a spot block duration. For example, if in a spot block of a 90 second duration we only have 2 minutes of content to replace, in that case the overfill value will become 30 seconds. In case there is a limit the streaming service will decide to break the content and return to the normal stream. Overfill limit cannot will not exceed Stream History limit. The minimum amount it can be set on is 0 seconds and the maximum 600 seconds. The default value is 60 secs.
...