The phrase "does an about face" can be seen as an idiom meaning a complete reversal of one's position or opinion. There are a few synonyms that can be used to convey a similar meaning. "Flip-flop" is one, implying a change in stance or attitude. "Reversal" is another, indicating a shift in direction or belief. "U-turn" is also a common synonym, suggesting a complete change in course or decision. "Turnaround" can also be used to describe a significant change in perspective or direction. These synonyms provide alternative ways to express the notion of making a sudden and total change in position or opinion.