Did any of the affected photogs replied to his sms to let the organiser know that you are close to the location already .... ?
If the organiser know there are 5 photogs already close to the location, the base on the stated min ration of 4:1 ... the shoot should carry on ...
Now if the models were not already cancelled and/or are nowhere close to the location, then it may be a different story ...
Well... heres my sms reply when I got the shoot cancellation sms...
"U must be kidding me. I am already on my way." :sticktong