Oui, its the one I believe is
The short sections are not part of the platform and aren't to be used. I suspect they stem from the days when slam door DMUs operated on that route, I know stories exist of one peak time train that had to draw forward to enable passengers to alight from the rearmost vehicles. The only way to keep the train fully in use would be to operate it local door from the front, and then run along the outside opening and then closing each door manually, that would probably lead to dwell times of approximately 3-4 minutes so wouldn't be acceptable.
The reason the 222 hasn't been sent is due to it falling foul of the rules of timetabling services. It needs to be double manned (2 x Drivers and Guards), and it needs 90 second dwell times minimum at each stop, which would put it overtime at stops between Manchester and Liverpool, it also needs a 7 minute dwell time at Sheffield to enable the driver to change ends, which busts the path for the service. That's why it hasn't operated for the past couple of years.