I think it varies according to local protocols and individual cases.
I had 3 monthly outpatient check-ups for a while and then 6 monthly outpatient check-ups since I finished 'active' treatment in Spring 2010, these have alternated between oncology and breast surgery. I've had annual mammograms and expect this to continue indefinitely due to genetic predisposition.
Nope, annual check ups are the norm and that is only for five years. After that you go back to the regular screening program. And it only consists of mammogram and ultrasound unless something is found, no other scans are done as standard.