Please remember that White Balance is really only Color Balance. Changing the setting on your camera won’t help with focusing or hand-holding
shutter speeds. In the film days, the only way to correct a color cast was to attach a filter to the front of the lens. A magenta filter was always added when shooting inside under florescent lights that were the usual light source in offices. Without it, people looked as if they had spent too much time on the Batman ride at Great America. Whichever setting you change it to, the WB will remain until/unless you change it. There is no default to anything. Check out these shots of a Chicago Botanic Garden van. It’s about 9:30 pm. Camera setting: 28mm, f1.4 @ 1/15th, ISO 800.