i was curious how i clear all the bakcpacks on my server for the next wipe. everything saved threw me wiping the map

My guess is that you would delete all the information in the Backpacks Data.json file, But confirm it with dev first,

Unless a command to do so is listed on a plugin's page, then you'd need to either unload the plugin and delete the associated data file else do it when the server is shutdown.

There is an option to clear backpacks on map wipe in the configuration file.