diff --git a/Marlin/src/module/ft_motion.cpp b/Marlin/src/module/ft_motion.cpp
index b7677df99f..af6b24b5c4 100644
--- a/Marlin/src/module/ft_motion.cpp
+++ b/Marlin/src/module/ft_motion.cpp
@@ -389,8 +389,11 @@ bool FTMotion::plan_next_block() {
       stepper.last_direction_bits.hz = current_block->direction_bits.hz;
     #endif
 
-    // Cache the extruder index for this block
-    TERN_(DISTINCT_E_FACTORS, block_extruder_axis = E_AXIS_N(current_block->extruder));
+    // Cache the extruder index / axis for this block
+    #if ENABLED(DISTINCT_E_FACTORS)
+      stepper_extruder = current_block->extruder;
+      block_extruder_axis = E_AXIS_N(current_block->extruder);
+    #endif
 
     const float totalLength = current_block->millimeters;
 
diff --git a/Marlin/src/module/stepper.cpp b/Marlin/src/module/stepper.cpp
index 86ad562e8c..82ba8d84f9 100644
--- a/Marlin/src/module/stepper.cpp
+++ b/Marlin/src/module/stepper.cpp
@@ -3623,7 +3623,24 @@ void Stepper::report_positions() {
       DIR_WAIT_AFTER();
     }
 
-    // Start step pulses. Edge stepping will toggle the STEP pin.
+    /**
+     * - For every axis drive STEP pins
+     * - If any axes lack DEDGE stepping:
+     *   - Wait for the longest required Pulse Delay
+     *   - Reset state of all non-DEDGE STEP pins
+     *
+     * The stepper_extruder must be pre-filled at this point.
+     *
+     * Emits macros of the form: [XYZEIJKUVW]_APPLY_STEP(state, ?always?)
+     * For the standard E axis this expands to: E_STEP_WRITE(stepper_extruder, state)
+     *
+     * TODO: For MIXING_EXTRUDER stepping distribute the steps proportionally to the
+     * E stepper drivers' STEP pins according to pre-calculated Bresenham factors.
+     * So the events are timed just like normal E stepping; only the STEP pin varies.
+     */
+
+    // Start step pulses on all axes including the active Extruder.
+    // Edge stepping will simply toggle the STEP pin.
     #define _FTM_STEP_START(A) A##_APPLY_STEP(step_bits.A, false);
     LOGICAL_AXIS_MAP(_FTM_STEP_START);