Possible Clues:

• Mix drink when eating fish
• Fish trapped in drink? Big change needed
• Shock Arab leader, say, riding horse
• Dine without fish during revolution
• Radical re-organisation
• Get fish in to eat for a complete change
• Major reorganisation
• To dine without fish is a radical reform
• Big reorganisation that gets everybody rattled?
• Jolt drink - something fishy in that