I purchased advance train tickets, which are non-refundable, on-line, and when I printed them, I realized that I wanted Premiere class tickets, not Tourist class tickets. Is there any way I can change those tickets to Premiere class tickets now? It is for a 3 1/2 hour trip from Granada to Seville, and I think we would be a lot more comfortable in Premiere class, wouldn't we?

did you ask this question of where you purchased them from - that would be the only definitive answer??? I think it you want to upgrade it is never a problem - more money for RENFE - is there no contact info on the site? Just curious. Thanks.

I think you need to ask Renfe about it. I suspect that you will have to either live with your mistake or pay for entirely new tickets.

On the other hand, I did a number of train trips in Spain last summer and there was nothing wrong with Tourista class seats. Maybe someone who usually travels first class will feel uncomfortable, but I had no complaints.

The longest trip I did by train was slightly under three hours. I did the Seville to Granada trip by bus and there was nothing wrong with that either. Both the trains and the buses were clean.

What type of Tourist Class tickets are they? If they are Tourist Plus, then you will be in the 1st or business class coach where seating is 2 +1 and not the tourist coach where the seating is 2+2. The tickets should show the seats you're been assigned.

The train from Granada to Seville does not serve food as it is not a long-distance AVE, so there is little difference in the class of travel, if you have a Tourist Plus ticket.

You can go to the station in Sevilla the day before your scheduled departure and try to exchange the non-refundable tickets, but it's doubtful they will do it. If they do, then you will have to pay the difference of what the tickets cost and the walk-up fare, just like the airlines. It may be easier and less expensive just to purchase new tickets and toss the others.

I am unable to quite grasp what you say as these are MD trains with no class differential. I do not think you purchased these tickets from RENFE as you are talking of Premiere.
And due to work on the network you will be changing to a coach for half the journey.
You are wasting your time

I agree, nonrefundable/no changes means exactly that, it isn't complicated nor confusing. Except for the fact that that train doesn't have classes and Premiere isn't a Spanish rail class, either. The RENFE site clearly states that route is a bus, also.