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Most likely, yes; however, it depends on how the apps are implemented. So we highly recommend reaching out to the app vendor to ask if the app data is restorable with the product backup.
Can I automate the backup download as well with Admin Kit?
No, unfortunately you can not. The feature request is tracked at https://labs-support.atlassian.net/browse/AKIT-4, but it will not be available in the foreseeable future.
How can I proceed the backup restoration?
No. As the restoration scenario varies depending on the site usage, you maybe want to reach out to https://support.atlassian.com/contact/.