Ah got it! So the key is, to look at the symbol to the left of the setting number. A '!' means edit in progress. When you press the 6, in this case, the symbol changes to '*' meaning edit not in progress (and cancelled). However the '*' symbol seems to mean something else during the WRITE operation. If I press WRITE, after modifying the setting, I see WRITE STAGESET [*0-6] even though the operation is not complete. PS. I see that I can alternatively press 7 instead of 6, and this will change to 0-7 and cancel the edit.