Is this a trend across the whole country, or just in some areas?
Actually, I think that this might be more specific to England/Wales. I live in Scotland and see no great rush to get back to Poland. Most Poles I speak to say they will be here another 2 years or more but see no sense in heading back to Poland before then. Although, I don't doubt there are some heading home. It's just not happening in great numbers, at least not in Scotland.
Scotland needs all the workers it can get I think...
True and there are topics about this about the forums. Yes, Scotland lacks workers in certain fields.