FOBT is recommended every 2 years from age 50.
However, if the patient has had a colonoscopy, the decision regarding the next colonoscopy is based upon the findings of that colonoscopy. Otherwise, FOBT is indicated 4 years post colonoscopy.
The following link is part of the Northern endoscopy guidelines and provides an excellent summary of the principles of managing anticoagulants around gastrointestinal endoscopy:
Anticoagulation guidelines for Endoscopy