(As a proactive measure against COVID-19, this event has been canceled in 2020.) Knox Heritage has combined its Summer Suppers and Scruffy City Soiree into one event in 2020 because of the restrictions on gatherings during the summer due to COVID-19. This fall, head to Tim and Deanna Hill’s Rivershack Farm overlooking the Holston River and the Great Smoky Mountains. Enjoy a simpler time and celebrate the end of summer under a big sky with an old-fashioned barbecue extravaganza. Tickets…