Largely they would be, because again, the employer relationship remains. The secondment is an agreement between the government and the international organization.
Then there's a third category, which is more of a case-by-case determination, and that's the category where people take a leave without pay. They're not really sent by the government; they're taking a leave without pay to pursue that, and that's more case by case.
But the first two categories are fairly clear. The first one is like any other expatriate; the second one would be treated like a crown servant.