Booking a seat in the direction of travel (when train reverses)

[VT 390]

If I want to reserve a seat on a service which reverses during its journey (such as Holyhead to Cardiff or Mallaig to Glasgow) but I am travelling on it after it has reversed should I select backwards facing when booking the seat so that it is actually forwards when I use it.
This may seam like a strange question but I prefer to travel forwards (I know some operators can not guarantee this) but I am not sure if the reservations are all placed at the start of the journey and then become the wrong way round later or whether they will be placed in the correct direction for each specific station.
Thanks

 

[Mag_seven]

I am not sure if the reservations are all placed at the start of the journey and then become the wrong way round later or whether they will be placed in the correct direction for each specific station.

Generally the former (which I've highlighted in bold). Particularly applies to reservations with paper reservation slips.