Christmas Eve morning, the Level 1 charging cable will not release; press, squeeze, yank, wiggle, no luck. Lock, unlock, repeat, repeat, same story. In a hurry, so transfer the family to the SO's ICE, as, with amazing foresight, I had parked my backup ICE farther back in the driveway thus blocking it in, duh!
Christmas morning, more time, try again, same story, so try pulling on the blue release tab behind the passenger door, but it won't budge, so resort to a leveraging with a claw hammer, still no luck, and afraid to break it if I pull any harder I bail. Press the God button, but She says to call my dealer in the morning, so:
Boxing Day morning, try again, still no luck, so call SF BMW, but of course all the gearheads are off till Monday, so out of desperation I heed the words of Jim DeB: "I sprayed it [WD-40] into the locking pin above the electrical socket. Then, lock and unlock the car a few times to work it around." Ding! ding! ding! after a bit of wrestling the damn thing released and I have my i3 back. (They should have called it Wrestling Day.)
I have a very early model and had the latest software update installed a couple of weeks ago, but I suspect this is more of an elementary hardware issue, with dry metal sticking to dry plastic and eventually released by slippery WWII technology. Still, I will take my i3 in to SF BMW and hope they can offer me more succour than "never leave home without WD-40".