On arrival at the dig-face, after some consideration, a slight change to my original thoughts. I decided to remove a large chunk of rock that currently forms the 'floor', we should then be at the same level as the potential connection. There are a couple of rocks at ceiling height that we'll need to keep a watchful eye.
Drilled 7no. hole, relatively evenly spread, c.350mm-550mm depth due to variable thickness of rock and the height to ceiling. It took a bit longer than usual mainly because I needed to keep changing the drill bit, and pay attention to the drop down into the Tuck Shop.
The evening's task was brought to a satisfactory conclusion from Stal Bend, where a rumble of falling rock could be heard. Plenty to shift on the weekend.