The reduced amount of water reduces yields because the vines can’t fill the grapes as much as normal. The reduced yields make it that much easier for the heat to ripen the grapes as well. The combination of the two means that many wine growers have to harvest their grapes earlier than normal.
The Pollak Vineyards facebook page indicates they started harvest on August 10, 2 week earlier than normal. (Also note that rain during harvest occured, which is not helpful to wine quality).
The Cardinal Point facebook page indicates harvest was underway by August 24th but does not indicate the date it started.
The article indicates decent grape quality despite the low yields. Next years tastings will determine that!