SBE12 - Keep Data for 4 Weeks append period

Append period: Starts from the time when the first backup is written to media. Media will become appendable after writing some data to it (if media set settings permit). Blank medias are only overwritable not appendable. 

You have media1,media 2 in SCRATCH media set.

Job using media set Test started on Aug 1 and moved media 1 from scratch to Test set and wrote the backup data to it. So media 1 will become Appendable till Aug 7th. If the same job running again on coming days with Append to media setting, then the same media will be used till 7th (allocation time is also important). If it becomes FULL before that, then media 2 will be moved from SCRATCH to Test set and will be used for backups.

Let's say the media doesn't become FULL and was used for all the backups till it becomes Not Appendable i.e 7th. So Overwrite Protection starts from there and the media will be overwrite protected till 4 weeks from there on. 

If the media becomes FULL on Aug 5th, Overwrite protection starts from there and media will be overwrite protected till 4 weeks from there on.

Overwrite protections will ensure all the data (including last written) on media will be protected for mentioned perioed. So if a media set is configured with append period 6 days and OPP 28 days, then the media associated with that media set will be overwrite protected for a maximum of 34 days and minimum of 28 days.