What we’re expecting
Apple Watch already uses LTPO. Its successor is HMO, high-mobility oxide OLED, which draws less power. The Elec reports Apple is evaluating LG Display HMO panels, with the 2027 Apple Watch the likely first product to ship it. LG Display still has to validate it for mass production, so this is not a Series 12 feature.
LG Display is reportedly being evaluated to supply a new OLED panel for Apple Watch, one that cuts power draw without dulling the screen. Earliest it could ship is 2027, so Series 12 is the target. That's a year-plus out, and being evaluated is a long way from confirmed.