Usually something will have been recorded prior to it being released… it’s hard to release a recording that will be recorded in the future. 
Someone was working on a Picard plugin to look through all Releases a Recording appeared on and set the “original release date” based on that, rather than only looking at the Releases in the current Release Group. See:
Note that there’s also a “Tango.info” plugin which might also help you with what you want? I’m only slowly starting to get into tango music myself (my girlfriend is an avid tango dancer), so I haven’t tried that plugin out myself yet. 