When does Petticoat Junction return?

Petticoat Junction is one of three interrelated shows about rural characters produced by Paul Henning. The series was created upon the success of Henning's previous rural/urban-themed sitcom The Beverly Hillbillies (1962–1971) The success of the series led to a spin-off, Green Acres (1965–1971).
The show centers on the goings-on at the rural Shady Rest Hotel. Widowed Kate Bradley (Bea Benaderet) is the proprietress. Her lazy but lovable Uncle Joe Carson (Edgar Buchanan) supposedly helps her in the day-to-day running of the hotel. Early on, much of the show also focuses on the Hooterville Cannonball, an 1890s vintage steam-driven train.