Yeah, what they did not expect is the US blocking all exports. All vaccines had to be flown in from Europe, even so the same vaccine was produced just a few miles across the border.
Evidently, Canada didn't prioritize Q1 delivery dates. From Our World in Data [1], Canada's total dose administration fell behind the EU during February/March 2021, as Pfizer's European production facility went offline for expansion/refurbishment. The dose-delaying recommendation discussed in this article became official in March, at the peak of the 'vaccine gap'.
However, the overall procurement strategy was a success even in comparison to the EU. Canada's total dose administration rate caught up with the EU's by April at 25 doses/100 people, and during the spring/summer when vaccines became available to the general public Canada had greater availability.
From contemporaneous reporting, it seemed that in summer 2020 Canada believed manufacturers' assertions that they'd have vaccine production ready by 2021Q2.
In general, Canada's vaccine procurement strategy was successful, and the 'gamble' on second-dose delays discussed in this article proved useful at expanding availability among the general population. Complaints otherwise tend to focus on the US comparator (neglecting its effectively nationalized industry) or come from partisan political attacks.