Yes to do that you should set following flags on "Source files" panel:
- Include only if "Archive" attribute is set
- Clear "Archive" attribute
So on the second start of this task only changed files will be packed.
You can create one task for full backup, for example - once a week.
(In this task you should set only second flag: "Clear "Archive" attribute")
The second task with both flags set for every day start. So In this case only changed after previous backup files will be packed.