VANCOUVER -- B.C.'s top doctor is apologizing to residents who had scheduled appointments for a second dose of COVID-19 vaccine postponed as a result of the province's decision to extend the gap between doses to four months.

Provincial health officer Dr. Bonnie Henry issued the apology during her live briefing on the coronavirus pandemic Thursday afternoon, saying the province's communications "weren't able to keep up" with its decision-making.

"I will regret and apologize to those communities, to the long-term care homes and to the individuals who had a second dose scheduled that had been postponed," Henry said. "I know that came as a shock for many people."

The province made the decision to extend the gap between doses after reviewing data on the effectiveness of the vaccines that have been administered in B.C. and elsewhere around the country and around the world so far.

Henry and Health Minister Adrian Dix announced the change to the recommended schedule on Monday. On Wednesday, Canada's National Advisory Committee on Immunization issued its own guidance recommending a four-month gap between doses. 

The provincial health officer said B.C. had to make its decision "rather rapidly" over the weekend specifically because many second-doses of vaccine were scheduled to be administered in the coming days.

"We are coming up to a time this week, where there were tens of thousands of doses of vaccine being scheduled for people to receive their second dose," Henry said. "That would have left us with very little vaccine to be able to continue our need to protect more people in more communities around the province."

So far, B.C. has administered almost 300,000 total doses of COVID-19 vaccines. Of those, 86,746 have been second doses.

Henry said the postponement of second-dose appointments would allow B.C. to vaccinate more people with a first dose more quickly.

"Please know that this (decision) was made in the spirit of understanding data and maximizing the benefit to all of us," she said. "That dose you didn't receive on Tuesday or Wednesday or today is now being administered to a community member, to another member of our family, our community here in B.C., to protect them. And ultimately, it will bring us all closer to getting to our post-pandemic world."