Well they could have a sophisticated auto-scaling system that only pays for capacity as needed. Or they could have some lone IT person turn on a bunch of servers, configure a load balancer, then cross their fingers, the morning of.
Does it really need to auto scale for a well known and understood usage? If dominos can do it for the super bowl surely the irs can provision for annual fillings
Yeah, the first peak around Feb 1 is almost a mirror image of tax day. You could load up for first peak, ramp down for the trough, then load back up again for the “deadline” (not actually a deadline). But you’re taking about 100s of times more scale, not 10s.