I think somewhere around every 3 years is the benchmark unless you had cancer, low or high grade dysplasia prior to surgery and/or a history of cuffitis since takedown. In the latter case, you should be going annually for scopes and biopsies. I go annually as I had an indefinite diagnosis for low grade dysplasia on my colectomy pathology and cuffitis on and off since takedown. I would, however, be very happy to only go every 3 years as a pouchoscopy with biopsies is an invasive procedure that does carry some risks.