Central Maine Power Co. line workers were reporting to work with overnight bags, some Emera Maine crews from northern Maine were being staged Downeast, and Time Warner Cable workers were stocking extra equipment in their trucks Monday. All were part of last-minute preparations by utility companies bracing for an expected blizzard that could bring down wires and poles and interrupt service. “We’ve been working on this for several days,” Gail Rice, a spokeswoman for CMP, said Monday.