Safely Upgrading Server Version

Hi, we are currently running a self-hosted instance of:
PB version 5.17.3 (and associated dependency versions)
Ubuntu 20.04
Apache 2.4x
PHP 7.4.3
MariaDB 10.5.17
WordPress 5.7.6

We are looking at upgrading to PB 6.15.0 and all related PB and stack dependencies. Is there anything we need to do (other than backups) to safe-guard existing content. Will it upgrade just fine as part of this process?

Would it be a good plan to first upgrade to the latest version of 5.x.x first and then move to 6.15.0?

Troy Welch
Innovation Developer,
Thompson Rivers University