This is easy for me, since it was May 8 - 50.6 miles in 3 hours, 4 minutes. I'm fortunate that, except near the beginning and end of the ride, there are only a couple of lights (they were green that day), so this was a true 50 miles in the saddle, with my feet clipped in the entire time. A couple of times I had to slow to about 8-10 mph, but o/w it was nonstop pedaling.
If the weather cooperates I'll do my first metric century on Saturday, though I expect to take a couple of breaks at rest stops, since I'll be riding with my wife.