Tracking his day-to-day movements, even if he should arrange to get to an airport in secret? Extraordinary. Do you have a link for that?
What I meant was the has a much broader choice of flights and even airports now. The odds seem to more in his favour now, should he wish to move.
Though actually, why would he? I don't see any advantage for Snowden from relocating to the same show, but in Venezuela or Argentina.
Both tasks should be business as usual for such huge secret service.
CIA had a lot of time between them and now. It also have a lot of resources and his movements are likely to be top priority for them. Them knowing he boarded a plane is real risk for him.
I do think that would be an achievement while he's under the wing of the Russian government. But what do I know?
What's really extraordinary is that gpvos knows for sure that it's not only doable but is actually happening; and is willing to share this intel with us. Or they seem to know; no citation to support the claim has been provided yet. It could just be internet BS.
For the rest: what watwut said in a nearby comment. I'm just extrapolating from things like the Evo Morales incident.
Submarines would be too expensive. He's not worth that much to Russia, Argentina or any other country.