In a decision not widely publicized, the WTA Tour has decreed the time between points for the rest of the season will be 25 seconds.
The rule book (last updated in August) still has it at 20 seconds. Since the US Open a year ago and introduction of the serve clock, the Grand Slams upped their own rule from 20 to 25 seconds.
Nao Hibino, before she defeated Genie Bouchard in the first round of the Hiroshima tournament Monday, asked the umpire to clarify. But it came from her, not the official.
Generally, the women rarely violate that rule.