Walked up in the morning, having had a tooth extracted the previous day - I promised the dentist that I would avoid strenuous activities for a few days and also not cave if it was raining (he was very concerned that we might underestimate the flooding risk underground!). Went to look at the remaining lead in 16-JB-01. This time we had a rope so started it on the ledge overlooking the chossy chamber, avoiding the dodgy climb, I put a bolt in and Olly went through the slot while I fetched the survey kit. Olly got down with a natural rebelay to a small aven/chamber. This led to a second connected similar aven/chamber, but no train tunnel passage sadly. We each climbed up in different places, my climb from the 2nd chamber looked to connect with the second slot near the pitch head. Olly's from where the chambers join became an inlet. Surveyed and derigged out. I carried gear up the climbs, while Olly had a final look in the chossy chamber, and found us another lead for the next trip.