You want to implement a 28-day backup cycle.

The scenario that uses the least storage for a 28-day backup cycle would be:

Incremental backup, log backup: Incremental backups store only the changes since the last backup, significantly reducing the amount of storage required compared to full backups.

References=This backup strategy is recommended in SAP HANA backup and recovery guides, which highlight the efficiency of combining incremental backups with log backups to minimize storage use while ensuring data integrity.

Backup and Recovery