I haven't heard any reports of the night bite turning on yet. A guy I talked to yesterday said he saw stripers jumping while he was taking his grand kids out crappie fishing. I would assume the bite is on.
Going through my notes I found the temp range of 60 to 75 degrees is when the night bite is good. Back in 2007 the water temp was in the 60s early April and people were reporting some hits between 10pm and midnight. The water temp of Cumberland is in the 60s now.