We have a an app that is in production and it has email notifications from postfix in it.

An example of email notifcations could be:
johnM@yahoo.com "you created record 123"
paul@hotmail.com "you created record 456"
george@gmail.com "you created record 789"
ringo@gmail.com "you created record 246"

We want to apply a lot testing data to the application for testing purpose however we do not want to spam our users to death.

We need to control each email to send it to a new location instead of the user.
An example:

johnM@yahoo.com > tempaccount@hotmail.com
paul@hotmail.com > tempaccount@gmail.com
george@gmail.com > tempaccount@hotmail.com
ringo@gmail.com > tempaccount@hotmail.com

Would this best be done with a virtusers table ( and how )?
Would this best be done with /etc/aliases ( and how )?

This is in later versions of Redhat ...
Later version of Postfix.
Later, timfox123