Marking the waterline
As Steve prepares to paint the hull, he realises the waterline doesn't seem to be level after all the moves since 2007.
Using a long plastic tube filled with beetroot stained water, he works out the line and jacks up the boat fore and aft . . . then she also needs moving port/starboard.
Just to be sure, we find a photo of her as she came out of the water in Spring 2007 and compare it with her now in the tent.