The most recent information I have seen is that ERTMS is due to go live 'in a couple of weeks'....but we have seen that before. It seems close, but has been for a long time. The cambrian crossing ( Cae Pawb) is one of number of bits of the jigsaw to finish, but as I have tried to point out, once the basic railway is passed it will have limited capacity ( or the one platform at Port actually) for WHR trains if the FR runs a full 3 train service.
Equally, there is no room for late running, meaning the possibility of a 'knock on' to other parts of the system is high, hence the step by step approach and see how it goes. We will run the winter trains to HyL, and at half term some trains over the entire route. As the FR is not running due to the bypass bridge work it is a good time to 'experiment', but once the FR reopens in March we have to take care not to affect other services.
Only when the cob is widened and a second platform for the WHR built will there be any flexibility in operation, and we have no idea of traffic patterns either...time will tell us.
Regards
Peter