CALGARY -- The first day of bookings for the AstraZeneca vaccine went by without website crashes or jammed phone lines, a success for a sometimes stressed booking system.

Wednesday approximately 53,200 Albertans under the age of 64 became eligible to sign up for the newly approved vaccine.

Albertans born in 1957 and First Nation, Metis and Inuit born in 1972 were able to register.

By late afternoon, Alberta Health reported 12,179 people had signed up. That works out to roughly 23 per cent of eligible people.

64-year-old Wayne Jacques of Claresholm says he had to wait first thing this morning and was initially denied by the online system. He later booked by going through 811.

"I won a trip to Lethbridge for tomorrow," he said with a laugh Wednesday. "It just feels so much better!"

On Thursday the province will open vaccine registration to anyone born in 1958, with a new year available each day until all 58,500 doses of AstraZeneca are spoken for.

"It really does depend on what the uptake is in each birth year cohort," said CMOH Dr. Deena Hinshaw.

Another shipment is expected, but it's not known how many doses or when it will arrive.

AstraZeneca is approved for adults under 65 and is being recommended for people with no significant underlying conditions.

Alberta Health Services says it has expanded its website and call centre capacity to allow for 5,000 people to book each hour.

"Albertans in the target age group can choose if they would like to receive the Covishield/AstraZeneca vaccine now or wait until their sequenced phase to receive one of the mRNA vaccines (Pfizer or Moderna)," said AHS in a statement.

Alberta is not using the AstraZeneca vaccine on people who are deemed to be at a higher risk or people over the age of 65.

AHS encourages anyone who may be at risk of complications to speak with their physician about which vaccine is right for them.

With files from CTV's Jordan Kanygin and Stephanie Thomas