During the pandemic, the secretary of the Treasury Board Secretariat sent a letter to the public service to say that people could be a little more flexible with the usual rules, because of the pandemic and the need to react quickly. However, the letter also made it very clear that each department was responsible for fully documenting decisions and judgments to ensure proper accountability to Canadians.
That's where the big failure happened with ArriveCAN. The documentation isn't there to ensure proper accountability to Canadians. Going forward, I would expect the Treasury Board Secretariat to make sure that measures are in place in the event of another emergency to secure strong oversight and compliance with letters or directives.