The best place to start is with the SZ 5.2 Release Notes:https://support.ruckuswireless.com/documents/3138-smartzone-5-2-0-0-699-ga-release-notes
It shows that your three models of AP are still supported natively, (no patches necessary). It also
lists a number of new features that you may find useful. The SZ 5.2 Upgrade Guide, says you can
upgrade directly from your version of SZ now,https://support.ruckuswireless.com/documents/3139-smartzone-5-2-0-0-699-ga-upgrade-guide
...but there is a note, that data statistics will not be preserved thru the upgrade:
Data migration is not supported if system upgrades from release 3.6.x. Existing system and network
configuration is preserved, but data such as status and statistics, alarms or events, administrator logs,
and mesh uplink history is not migrated to the new release.