Satellite shots indicate that Spain is ash free. If I were you I would rent a vehicle, along with others in the same situation as yourself, and sharing driving start heading south. Yes, that means going through the Chunnel. And don’t delay! This situation is unpredictable if history is a guide.
This volcano has been known to erupt for as long as two years. In the 18th century, one eruption’s ash output was so great that the following summer never happened - Europe faced famine because it was too cold to grow food!
Would be a good plan, but European airspace is closed, too.