Quick question on upgrading plugins in the mu-plugins directory

Hi,

New to WPMU Dev Premium and have installed a bunch of excellent plugins (well worth the money!)

My question is how do plugins in the mu-plugin directory get updated? Since they do not appear in the plugin list on the admin section (which easily checks and allows for plugin updates when they are available), do I have to come back here and manually see if there is an updated version for one of my installed wpmu dev premium plugins available?

Given the value of the plugins, I wouldn't mind at all, just need to know if it needs to be on my to-do-list periodically. :o]

Thanks,

Rone

PS - I search the forums but only turned up results related the actual "upgrades" plugin.