I came back in the dark a few weeks back and although I normally fit under it I spied a red light. When I got closer I saw the bridge was closed to traffic and there were workmen on it so thought fair enough, they're stopping boats going under for safety.
A workman saw me waiting and hailed over, apologising and said they were running behind schedule but would be opeing soon. Well I waited about 30-40 mins eventually.
Only as the bridge was about to lift did I realise I had been looking at the wrong red light! There is a small one near the inshore lifeboat station - that became obvious when the real red traffic light came on for a few moments before going green.
Doh!