If you're referring to the nighttime Extra Magic Hours, then yes, the test phase ran through 5/22.
We were at MGM on 5/18, and it was about what I expected. While we actually did view Fantasmic that night, I suspect the rides were virtually deserted from 9 - 9:30pm while the show was running. But, at 9:30, the crowds emptied onto Sunset and many queued up for RNR and TOT. Obviously the posted wait times were not correct due to the immediate influx of guests, but I have to think that some of those folks waited up to an hour in line.
FastPass was open and the initial return times were very short. We got passes for RNR that allowed us to ride after only 20 minutes.
This was intended to strictly be a test program. E-Ride Nights at MK have already been published for June and July, so they are going back to the original EMH schedule (mornings only) at least for the summer. So we'll probably have to wait until the fall to find out if any permanent changes are forthcoming.