A co-worker retired recently. You have been given many of her contracts toadminister. One of these is a contract to replace the roofs on several Government buildings in the area. As you start going through the stack of mail that she had, you find a FEDEX package containing a letter from the roofing contractor. In the letter the contractor states that the COR on the project had instructed him to make a change tothe specification of the roofing materials to withstand an approaching hurricaneforecasted to hit within days. Due to the impending hurricane, the contractor statedthat if he did not hear back immediately, he would proceed with the COR’s requests. What type of contract change occurred?