Stratesave allows changes in macro, while it is in service and backups are executed after it. You can, for example, modify storage-locations, insert additional directories and periods in backup plan etc.
Also differential backups, which are based on another backup with longer period, continue to work even if macro is modified. You only have to pay attention to activate the new settings, by reloading macro in backup (or restarting backup program).
If database backups are defined, significant changes in macro with regards to databases require a full backup of highest period to be run next.