Westbahn train ticket booked online from Salzburg to Vienna Westbahnhof

It looks like that may be a open ended ticket? I've not used that website to purchase train travel before. In the past I've purchased directly from the Austrian rail website or the DBahn website. Maybe someone more familiar with this company can help? When I went to that website I didn't even see a time to choose for the tickets.

If you only paid 26 EUR, you don't have a seat reservation, since they are an additional 5 EUR. This is from Their FAQ:

How can I make a seat reservation?
Up to two hours before train departure from the departure station you can make a train bound seat reservation and shift or cancel your reservation. A seat reservation costs € 5,-.
When booking WESTbahn will suggest a seat for reservation to you. If you register for „Meine WESTbahn“ and log in you can change the suggestion to your desired seat. On your ticket PDF you´ll find the platform sector, coach number and deck denomination as well as the exact seat info. If you have any questions please address yourself to your stewards who will guide you to your seat.
Please note that reserved seats can be used by other travellers if they are not claimed within 15 minutes after departure.

Since the trains run every hour, I don't think they are really necessary, and since the train originates in Salzburg, you can arrive early and board as soon as the train is spotted on the platform and you'll have your choice of unreserved seats, Reserved seats should be marked with an electric indicator above the seat. Otherwise, proceed with the registration process and see if you can get done that way.

Normally, people just get on the train and take a seat and buy the ticket from the conductor when he comes around.

Thank You!