Not sure if this is doable but i would like to look at all the star and end date highlighted in the picture below and look for differences between each End and Start date to see when a person is available an not assigned to any projects. I would like the date range to be between 01/01/2019 and 09/30/2019 but the range will be expanded or changed as time goes by.
For example if a person is assigned to a project with the first set of start and end dates is 01/15/2019-02/01/2019 and second set is 02/15/2019-02/20/2019, the available date range would be 01/01/2019-01/14/2019, 02/02/2019-02/14/2019, 02/21/2019-09/30/2019.

The first picture has multiple records for each auditor but in he output i would like to have only one record for each as shown in the 2nd picture.

I am attaching a sample file as well.
Thank you in advance for any help or tips.