Read through the release notes. They document progressive improvements and the introduction of new features. Choose the last firmware version that offers definite upgrades or new settings/features and upgrade to that version.
If all subsequent versions read "...bug fixes..." or "...security features/upgrades...": they won't do anything to improve the functionality.
Learn and download Mavic Pro related apps, software, and manuals at the DJI Download Center
www.dji.com
Reading through them can be an education. For example: the release notes for the original Mavic pro will tell you when the 'auto-log out' restriction was first introduced (6th August 2017) and what it does.