Have the tunnels both been closed again then Phil? (I know they were both closed for a while)
We went last November and one was open, we walked through, because of the bend in the tunnel you can't see the far end so in the middle it's proper dark, if you turn your torch off.
I think the plan is to make the tunnel part of the cycle route.
The logs on the geocache placed in the tunnel seem to suggest it's still open too.
You're right about the road works though our route wasn't as straightforward as it might have been, still made a good outing though.