Graham Nash is postponing all 11 remaining performances on his fall tour, including his Saturday show at Humphreys Concerts by the Bay in San Diego. A statement released Thursday night on his social media pages cited COVID-19 as the reason. “We are sorry to announce that we have to postpone the remainder of Graham’s tour dates, effective immediately, due to a COVID outbreak in the touring party,” the statement reads. “The shows will be rescheduled as soon as possible. Stay healthy and safe out there!” There is no word yet on whether the postponed concerts might take place this year, or if they…