Android Motion Layout - textAlignment custom attribute

Question

I'm using MotionLayout and using it to animate a TextView that has two lines of text, in the center of the screen. Then I'm animating it to move to the left edge of the screen, and I want at the same time that this animation occurs to change it's textAlignment from center to viewStart.

I tried setting the custom attribute inside the Constraints like this:

<Constraint
            android:id="@+id/message"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            motion:layout_constraintStart_toStartOf="parent"
            motion:layout_constraintTop_toBottomOf="@id/title">
            <CustomAttribute
                motion:attributeName="textAlignment"
                motion:customIntegerValue="5" />

and inside the Transition block like this

<KeyFrameSet>
            <KeyAttribute
                motion:framePosition="0"
                motion:motionTarget="@id/message"
                motion:attributeName="textAlignment"
                motion:customIntegerValue="4" >
            </KeyAttribute>
            <KeyAttribute
                motion:framePosition="50"
                motion:motionTarget="@id/message"
                motion:attributeName="textAlignment"
                motion:customIntegerValue="5">
            </KeyAttribute>
        </KeyFrameSet>

But none of those tactics worked, and the text inside the TextView does not get left/start aligned and is always centered. How can I solve this?