Activating a Large Audience to Destination

HI All, --------------------------- I wanted to Export a large audience like 60 to 100 M to a cloud destination like blob with only 1 field like FirstName or email. --------------------------- The current dev and stage sandboxes have a limit of 4M max as the upper limit of engageable profiles. So is there a way to deduplicate the existing audiences to create a new audiences?. --------------------------- Approach Tried - 1. I have tried to use Audience composition rule builder. But there isn't a native option to do this? --------------------------- Approach thinking to try - 1. Make a FAC audience connection and create a large volume audiences. 2. Activate the large volume to destination ( I doubt even to activate, it comes under engageable limit. --------------------------- Let me know of any other ways. --------------------------- Thanks