I was having trouble getting the Update All to work for me but I think I figured out why it wasn't working for me.
When I tried to update a single plugin it told me I can't because the plugin was currently in use. I have a very involved pedalboard with many plugins. So I loaded the default plugin, which has only the gain plugin, and went back to the plugin store and hit update all and it worked!
So I guess... to insure that all plugins will update, you need to have a totally blank pedalboard before hitting "update all"
Is there a way around this?