All UK pensioners get WFA, it isn't means tested so the EU rules meant that if a retired person was claiming it before they emigrated they should still get it, just as they do their pension.
This changed recently on appeal so that all UK pensioners were entitled to it even if they had never claimed it in the UK.
That is why the rules have changed yet again and many, but not all, ex pat pensioners will no longer be entitled to from 2015.
I'm not sure how I feel about it - it IS part of the UK pension, after all.