Jobe,
I hiked the Bradford Ridge Trail back in mid-April just before Easter. It was my first trip back to Deep Creek in two years, and my first ever trip down the Bradford Ridge Trail. The wife and two young daughters made the trek with me. We didn't want to come down through Bowen Ranch and have to cross the creek in the spring high-water runoff.
The trail was in fine shape. The 8 and 10 year old girls navigated it better than their parents! Yep, the frogs were croaking and the waterfall at the top of the trail was flowing.
I don't know about the need for the adventure pass though. We parked our SUV at the turnout near the bridge. It was there all day without a pass, and no ticket was found when we returned. Of course, it was a mid-week day, and no other cars were parked or seen on the road while we were there. We did run into a Wizard loitering in the springs, however ;o)
-Gary