Comment 8 for bug 1136253

I can see two possibilities here:

- If there is no remaining defender around but some of stationed soldiers are away attacking an enemy site, it can pick one of them and use him as defender, thus preventing the fall of site. This would be quite rare scenario
- site can grab one of defending soldiers (stationed at some other site) just being around, reassign it to itself (change its home site to itself), the then it can use him as defender. But this would significantly change the gameplay.