I went back and checked, and I was thinking of TAR 15. When the teams went to Japan, there was speculation that they would then go to Taiwan, and then Vietnam, and there was some research that showed that there were flights from Taiwan to Vietnam. It didn't materialize, but my point today was that the one tweeter could legitimately be headed to Vietnam, and be on a flight with this season's new Racers.
That said, Phil has been spotted during the Race a few times, including at pitstops, during these last couple of seasons (Sydney, for one), but one spotting of Phil outside a pit stop that I can think of offhand was in the Penang airport in TAR 16. As I recall, that tipped off the Penang and Singapore legs during filming, as the Race had dropped out of sight. (Seychelles, anyone?)