The MTA says it has been stepping up the automation of its guinea-pig L trains without telling us. They started with night service, but have been pushing into daylight hours and now say it’s working round the clock. Interestingly, WCBS last night ran a report that the L has been skipping stops at night because of a software glitch — which an MTA employee readily admits. If the train brakes just a little too late at a platform, it can’t open its doors, and so just surges ahead. Suddenly instead of Morgan Avenue, you’re on Jefferson Street, and as the old commercials used to say, you can feel the difference. The MTA says they’re working it out, but you’d think they’d want to do that before expanding the automated service.