The thing about key reversal days in FX is when is the close?

Gotta pick a time and stick to it I guess, although the end of NY trade does make some sense.

Anyway - AUD key reversal day (there are more in other currencies today also, feel free to post in the comments):

The thing about key reversal days in FX is when is the close?

Key reversal days are said to indicate a change in trend (comments welcome on that also).