Print A surge of demand arrived in San Diego County Thursday on the first day that anyone age 16 or older could make a coronavirus vaccination appointment after four months of the supply being restricted by age, occupation or medical status. New rules did not just affect vaccine eligibility. Indoor and outdoor entertainment venues gained additional operating capacities Thursday though most organizations, including the San Diego Padres, say they are not quite ready to test the limits of what’s now allowed in the orange tier of the state’s reopening system. The frenzy started on Wednesday at UC San Diego, which announced that it had about 3,000 appointments available Thursday at RIMAC Arena and that those in the soon-to-be eligible group could schedule their shots. Ordinarily, it would have taken a couple days to fill those open slots. This time, it took five hours, according to Dr. Marlene Millen, one of the leaders of UCSD Health’s COVID-19 vaccine operations team.