Looks like the Army will have to do a "Stop Loss" on steroids effort.
Cooperative Engagement, not just boatfagging but watching certain private planes. They'll try to fly out to private islands or close to marinas. Might help to keep an eye on the "Executive Transport" charter planes. Nab 'em when they land or grab 'em while in Territorial Waters. No doubt they'd have a plan to stall permissions to board in International Waters by Flag Country. Here's Nat Rothchild's PLANET NINE, flag Malta. Trying to stop her on the high seas would require Malta's permission, red-tape stalling ability there.