Hi,
We deem foward mode is when you are sitting in the cab looking in the same direction as the forks are pointing.
If you are changing from regular forwad mode to side mode, the rear wheel turns to 90 first until it gets to the rear 90 degree proxy. Then the front starts to turn to 90 until they reach the front left wheel 90 degree proxy.
If changing from side mode to frontal mode, then the front wheel change to 0 degrees (0 degree proxy) then the rear changes to 0 degrees.

Hope this helps.