Now I've been out for a bike ride through the fields, I realize I forgot to mention set-aside land. (Fallow) Theoretically that's 5.4 e6 ha they could turn into feedstock land. In fact only part of it could be used, (very small fields aren't easy to use), it's not the best land (which is why farmers chose to set those fields aside), there are biodiversity problems (areas that have lain fallow for ten to fifteen years have become a relative shelter for flora and fauna), and regrouping some of them into larger fields for mechanisation/irrigation reasons would involve destruction of hedges, banks, and ditches.

I don't think it would change the basic point that 1st-gen biofuels from EU-grown feedstock aren't going to supply enough biofuel.