CALGARY -- It's already been a busy spring at Alberta's pharmacies and mass immunization sites, but Monday signals the start of what may be the biggest rush yet. 

Albertans born in 2009 or earlier are now eligible to book a COVID-19 vaccination. 

That includes everyone 12 years old and older, and those who are 11 but will turn 12 this year. 

As expected, demand surged Monday morning as bookings went live. At one point, more than 68,000 Albertans were queued up online to schedule their first dose. 

According to Alberta Health Services, more than 33,000 appointments had been booked Monday morning as of 9:45 a.m. and thousands of people were still in the queue awaiting their opportunity to book.

Appointments are available on the Alberta Health services website based on a first come, first served basis.

The province suggests residents book online, but the 811 line is still operational and Albertans can also book directly through participating pharmacies. 

As demand surges, things are also looking positive on the supply front. 

According to the federal government, more than 2 million doses -- mainly Pfizer -- are coming to the province before July 4. 

Previous deliveries have been delayed, but Premier Jason Kenney says, if all goes according to plan this time, every eligible Albertan could have their first shot by the end of June. 

The province is the first in Canada to offer shots to the 12-years-and-older age group. 

Manitoba and Saskatchewan have plans to do the same in the next two weeks.