You are right about thousands a day to remove a million in a year. Almost 2,740 if they work 7 days a week, or 3,831 if they work 5 days a week. Will they use airplanes or buses, and where will they be returned to and how or if received by destination countries?
Load them on ships, planes, buses and dump them back wherever they came from whether they like it or not.
I would like to see 10,000 a day but whatever the number it needs to start, many will leave on their own once it does.