CNN Reporting..
Of course this is news media so take with a grain of salt,
CNN Reporting that at 0130 local during scheduled flight hours the plane took a ~270 deg turn E-SE towards straits of Malacca
fmr NWA Capt. Dave Funk [14k hours on 7x7, dc9, USAF] theorizing the plane (crew) may have done dead reckoning nav due to an electrical systems total fail.
CNN saying the turnaround is "pretty much confirmed".