For the first part, you can define a calculation field and place it in your header in place of the static layout text. There are several different ways you can do this and some of the exact details will depend on how you've set up your table, but one such cacluation field would look like this:
Year ( YourDateField ) & " " & YourNameField & " Master Schedule"
As long as all records in your found set have the same year and name, this field will accurately display what you want.
...how do I create a field that shows the most recent modification from all of the records that have been sorted?
Define a summary field and set it up to show the "maximum" of your modification date field. Then it will show the most recent date for all the records in your current found set.
Thank you so much for your help!