Here's the scenario. Your Special Issuance Authorization expires in 2020. Your most recent Third Class medical, issued under the Authorization, expired in July 2018, and you have been relying on BasicMed since. May the FAA request additional information under the Authorization and "withdraw" the Authorization if you refuse, precluding your reliance on BasicMed? In October's Domingo interpretation, the Chief Counsel says no. "when an airman's special issuance medical certificate has expired and the airman is not in the process of seeking a new special issuance medical certificate, additional medical information is not reasonably needed for certification under§ 67.401. Consequently, the Federal Air Surgeon may not withdraw the Authorization based on the airman's failure to provide... " A reminder: this is general information. As with all serious issues involving FAA certification, a pilot faced this situation should seek professional advice to be certain it applies to him or her.