Use X3-turbo-AA by default

src/CrossPointSettings.h

@@ -226,8 +226,13 @@ class CrossPointSettings {
   // X3-only: when on, the AA refresh uses the 7-frame community grayscale LUT
   // (~130 ms panel time) instead of the OEM 53-frame LUT (~2.4 s). Mid-tones
   // run slightly darker than X4. Matches what papyrix-reader has shipped since
-  // 2025-11. Default off preserves OEM-fidelity grays. No effect on X4.
-  uint8_t fastAntiAliasing = 0;
+  // 2025-11. Default on — the 2.2 s/page win dwarfs the subtle mid-tone shift.
+  // No effect on X4.
+  //
+  // JSON key was bumped from "fastAntiAliasing" to "fastAntiAliasingV2" when
+  // the default flipped to 1: existing settings files with the old key are
+  // ignored, so every device picks up the new C++ default on next load.
+  uint8_t fastAntiAliasing = 1;
   // Text darkness (0 = normal, 1 = dark, 2 = extra dark). Default 1 preserves
   // historical AA rendering (both grayscale shades drawn in the MSB pass).
   uint8_t textDarkness = DARKNESS_DARK;

src/SettingsList.h

@@ -115,7 +115,7 @@ inline const std::vector<SettingInfo> list = {
     // (~2.4 s panel time, X4-accurate grays) for the 7-frame community LUT
     // (~130 ms, mid-tones slightly darker). See open-x4-sdk
     // EInkDisplay::setFastGrayscaleLut for trade-offs.
-    SettingInfo::Toggle(StrId::STR_FAST_AA, &CrossPointSettings::fastAntiAliasing, "fastAntiAliasing",
+    SettingInfo::Toggle(StrId::STR_FAST_AA, &CrossPointSettings::fastAntiAliasing, "fastAntiAliasingV2",
                         StrId::STR_CAT_READER)
         .withSubmenu(StrId::STR_MENU_READER_FONT)
         .withDeviceTarget(SettingDeviceTarget::X3),