Hectopascals have been around for some time. I well remember the original NOTAM which stated that the FDR (West Germany), the GDR (East Germany) and Malawi would adopt the hectopascal at midnight and abandon the milibar. It went on to say that the conversion ratio was 1 hectopascal = 1 milibar.
I think the date was 14 September 1984 and I was flying from McGuire to Frankfurt. Sure enough, the Frankfurt ATIS was giving the pressure setting in hectopascals on our arrival.
So, for the last 30 years or so the rest of the world has been missing out on hectopascals!