I push the lever the same amount in the other direction. The clock on the wall moves backwards!

The clouds and sun race past in the other direction! The cleaner walks quickly, as before, the exact same steps yet backwards! So it all works! I can come back again, I won't be trapped in the future!

Should I bring the machine to a stop? Or should I push it all the way? Or go back to when I started? Or do something else?