My kitchen staff are on strike and I have lunch booked for 50pax what should I do?

Wow, that's tough!
Can only think of a few ideas (not in order of doing them):
1) plunder your stores (or get in more this morning) enough ready to eat foods to make a gorgeous buffet. If you have enough time and supplies, cook one dish as a centerpiece for the buffet.
2) arrange a handful of cooking stations in your kitchen, give a cook and eat lesson as the lunch.
3) combine parts of #1 and #2, as best applies to your situation
4) announce to guests the reasons for the changes. Tell your clients, and offer them a discount versus contract....e.g change in menu, self service vs full service.
Good luck and success!

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