To do it en masse and coordinated like this…my guess is it's witness protection. You don't do this for cargo and you don't do this for group flights or low security or single point transport. This only makes sense if you're having a group of HVTs assemble under cover and fragmenting them away to different locations for their protection…and depositions.
You know…the Clintons are rumored to kill prosecution witnesses…so this is shrewd thinking. 2c fwiw.