I thinks that’s the key though - the argument is that the program should be shutdown, not that they should all be put on border patrol duty… assigning them to a random alternative post is going to make recruiting good new folks really hard.
But I'm assuming at least some percentage would be OK with it, and the ones who aren't would have to find new jobs. Very similar to when companies downsize one department, but try to find jobs for existing employees by giving them jobs in other departments. Some will take it, some will reject it, but it's a pretty fair outcome for all.