edit: I note you have done this, based on all available information I would do the same. We have the Emergency Schedule checked at the top of the IVR, so it's just doing an additional check of this schedule during the loop. I am redoing our IVRs at the moment.
You could do something like this
Transfer to Q
Loop every 10 mins, check the emergency schedule and provide feedback the company is experiencing unforeseen issues, or continue on hold music. This way the customer will only be stuck in the IVR for a max of 10mins.
