SURREY, B.C. -- For the second day in a row, drop-in vaccination clinics in the Fraser Health region saw hour-long waits Wednesday for people eager to get their shot.

At the Newton Athletic Park, some even camped out overnight.

The pop-up clinics are receiving mixed reviews. Some believe they are worth the wait, while others say there is confusion over how the lines are managed and there is a lack of information from officials.

Dr. Judy Illes is a professor of neurology at the University of British Columbia and an expert on the topic of ethics regarding vaccine rollout.

“We are doing the very best we possibly can,” Illes told CTV News in an interview Wednesday. “There is no playbook to this crisis and to the response of the crisis and we keep seeing on an almost daily basis a layering of crises.”

She says health officials are constantly having to adapt to a changing landscape, whether that be new variants of COVID-19 or new hot spots within health regions, adding that can be “messy.”

One of the factors driving the ever-changing rollout schedule is vaccine shipments. This month Moderna announced shipments to Canada would be smaller than initially promised. While from next week, B.C.’s allocation of Pfizer-BioNTech is set to double to 274,950 per week, with more than 1.1 million doses scheduled to arrive through May.

It’s likely more pop-up clinics will be appearing in coming weeks as the number of available vaccines increases and Illes believes it’s an “inventive” way to gain traction faster.

“I’ve seen the news today of people being frustrated at pop-ups,” she said. “Pop-ups making more vaccines available to people is better than not having vaccines available to us.”