Perhaps I have the wrong definition of BAR as I usually consider that to be the best refundable rate.

If you normally book non refundable rates then the night isn’t really 2-4-1 as take the last weekend in September the cheapest room at IC PL is £645 for two nights without breakfast non refundable. But the 2-4-1 rate is best fully flex price of £439 so it’s not 2-4-1 but rather c30% off. But £200 saving still covers the cost of ambassador.