Since you asked -- or maybe would prefer not to know -- here are a couple of photos that might help you to understand the contents of our new Rhosyfelin paper, when it appears. What we are proposing (Dyfed Elis-Gruffydd, John Downes and me) is that the deeper deposits at Rhosyfelin are partly rockfall deposits (see previous post) and partly a mixture of meltout till and fluvioglacial gravels. We envisage an environment very similar to this one, on the edge of the Russell Glacier in western Greenland. (You see similar associations of sediments in all glaciated regions.)
The essential features here are (a) dirty ice, well laden with sediments close to the ice edge; and (b) fluvioglacial sands and gravels laid down by shifting meltwater streams. There is quite strong relief here, but when the glacier has melted away, and when the ice has also melted out from within the ice-cored moraines, all that is left is an undulating surface of meltout till mixed with fluvioglacial materials. There will be some lodgement tills, but most of the deposits will have the characteristics of "flow tills" -- which have literally flowed or slipped down an ice surface and accumulated against the base of the slope. As I have said many times before, this is the sort of environment in which "anything can happen, and usually does...."
When the ice has all melted out, you may get something looking like this landscape of hummocky moraine:
This is near Bruarjokull in Iceland. Sometimes, close to existing glacier snouts, there may still be some ancient buried ice deep down beneath the surface. In other cases, you will get even less surface expression, and a subdued landscape of mixed till and fluvioglacial materials: