When I was pg with Liebling, it was having worked for 12 months prior (6 months would have you paid less, but not need to return) and for 3 months after returning. But that was to get the "higher" level of 90% of wages for 3 months, then down to 3 months at minimum payment, then 6 months of nothing. Had I not returned, I'd have to pay back the extra, but I'd keep the equivalent of 6 months at minimum payment. A similar thing happened with my cousin who worked in a different sector.

But different companies have different policies.