FastBound will automatically generate Multiple Sale reports after a disposition when they are calculated as required by FastBound.
These reports can be found in the Pending Multiple Sale list
There aren't any settings for business days or hours. FastBound learns based on the activity in your account
Which Items can Generate reports can be configured in your Multiple Sale Account Settings
This calculation does not mean that you no longer need to be concerned with whether you need to fill out a Multiple Sale form or not. It is still your responsibility to properly report Multiple Sales.