I would hazard a guess at around £1m a day, the bigger problem is forward booking which slumped in the last few days with all airlines.
Very few would be booking any trips for the next few weeks so the cash flow starts to dry up but the money (wages and so on) keeps flowing out.
coaching accross Europe wont be cheap either and they still have to pay someone else to take them over or under the channel.
Every cancelled flight equals a refund so money will be pissing out of the business if this continues into next week they will have to look at stemming these losses, that means wages!! sh1t