People are set to duck under desks and tables in California and around the world for an annual drill practicing ways to stay safe during earthquakes. Up and down the West Coast, the ShakeOut drill is scheduled to begin at 10:19 a.m. Thursday with a cellphone-rattling test alert from the region’s ShakeAlert earthquake warning system. For many it will be the second alert of the day, following an errant predawn message that hit some phones with a voice message announcing the test. The U.S. Geological Survey says that was likely due to a mix-up in time zones set in the test alert system. The real thing happened on Wednesday, however, when a magnitude 4.2 quake struck southwest of Sacramento, California.