Remember, when EE start, there are still day guests in the queues for all the attractions. Day guests are not kicked out of the lines at 9pm, if they are in line at closing, they stay in line. After 9pm, they will not be allowed to enter the queues. So, the first hour can still have 45 minute waits, as it is still a combination of day guests and the guests eligible for EE. Generally, after the first hour of EE at Epcot, wait times drop quite a bit.