On the second Thursday of every month, NOAA issues its analysis of the status of ENSO. This includes determining the Alert System Status. The best guess remains March.
But I have actually seen only a few signs of it starting to happen. But all the meteorologists agree that it will. Could they all be wrong? Probably not.
Will this La Nina transition quickly to the El Nino phase? That would be unusual but some of the models suggest this will happen. It seems likely that the ENSO Neutral Phase will at the very least have an El Nino Bias.