All Pursers and CSD's should be aware of this. They have been e-mailed and there are posters in the briefing rooms at T5.
The general gist of the trial is that it will be meeting flights from a couple of routes which are based at T3, those being VIE and HEL (if I remember correctly). The first bus will be allocated for CE customers only and will hold a maximum of 32 CE customers. If more than that, there will be a second bus for CE customers. ET customers will be placed onto subsequent busses.