As a player who uses manual or manual w/ clutch shifting interchangeably, I have had to bind the controller buttons for activating menus/events.
Unless you are using the absolute default controller settings, the rewind feature gets broken with the ability to back up only once.
Pressing the rewind button after one backup either - does not work at all - or enters into replay mode. In my settings, the rewind button has been left unchanged to Y on Xbox.
This serious bug has been present for so long and given this has been a staple FORZA feature, I am surprised it has not been fixed at all.