About 6,000 older Bitcoin mining machines in the US will soon be idled and sent to a warehouse in Colorado Springs where they’ll be refreshed and resold to buyers overseas looking to profit from mining in lower-cost environs. Wholesaler SunnySide Digital operates the 35,000 square-foot facility taking in the equipment from a mining client. The outdated machines are among several hundred-thousand it expects to receive and refurbish around a major quadrennial update in the Bitcoin blockchain....