But, you could have an issue copying the full chain of the source backup job you’re referencing. For example, if the source backup job chain you’re copying from is a week long, you would need to expand your interval to 7 or 8 days, or otherwise your interval setting would be out of scope. After your source full chain has been copied, you can set the interval to a lesser period...for example, 1 day. And this is assuming your source backup job runs at least daily. This would ensure you get the most current data from your source job. Let me know if you have further questions...and yes, it is indeed a bit confusing. I’m actually doing a series of posts here on the Community Hub regarding Copy Jobs :)
For more info on how Intervals work, review the User Guide here. And, if you wanna read my posts, you can start here.
Cheers!