Thanks Vilas. I enjoy reading your inputs -you clearly have great knowledge of the Airbus (much better than mine!)
I suppose you would obey which of the 2 restrictions was most limiting.
Eg If you were cruising high and had 240KCAS and M0.77, you could not lower the gear. Without getting my redundant CRP5 out, I guess to get below M0.60 you would have somewhere around 190KCAS - unlikely.
It might be interesting to calculate where M0.60 crosses with 250KCAS. Somewhere around 25,000’ I guess.
How academic can we get?