Some registrars put it through immediately, others like Namecheap will send an additional email follow up that asks if you want to approve immediately and transfer or wait it out. Approve, and it’s done right away.
If you read above, Dreamhost clearly states it can take up to 7 days. 5 is the normal average time period, theirs is longer, assuming there’s some foot dragging by them to hopefully convince you to stay.