We had train tickets, bought online, for a trip from Madrid through Oviedo ( train change) through to Ribadeo. We checked that our tickets, prepaid, were okay. We took the train to Oviedo. All was good. Then, in Oviedo, we talked to the lady at the service window of Renfe to ask about the platform for our continuation to Ribadeo was okay. The lady at the Renfe window said, it's a different ticket office, go upstairs and it will be fine. Look for a train labeled "Ferrol." We went upstairs, this is a change from the Renfe system to the Cercanias system. (Both are run by Renfe.) There were no trains that looked right. I sought out the Cercanias window, pointing out the trip info on our tickets, and she directed us to Platform 1. She said that the train we wanted would be labeled "Ferrol." We went to Platform 1 and waited. There was only 1 train that matched the departure time on our tickets. It did not match any other information. So we got on and rode it. The line route ended at Avilés. When we got off there, we asked at the window. No, there was no train going through to Ribadeo. We talked to the man at the window, he consulted with amother employee of the train system. He said there was no train from Avilés to Ribadeo. Fortunately he mentioned that there might be a bus going that way. We went 2 doors down to the bus station and got bus tickets through to Ribadeo. We had about 10 minutes to line up at the plaza for that bus (mumber 13) and then we were off!
So we have no idea how they sold us tickets to Ribadeo when they had no train going there. But we got there anyway.
So one never knows how things will work out. Thanks to the Alsa bus, we got to Ribadeo in time for our reservation.