train reservation to Munich

I just got to the payment page for 2 seat reservations for that train at www.bahn.com/en. Cost is 9 EUR.

yes, thank you, I am also able to get to that page and select 2 seats but then receive a message that they are not able to award a reservation. Assuming that this is not a question of how to use the web site, I guess my question is what does this mean, not having an assigned seat but having a ticket. Can we still get on the train or is it sold out?

You can still ride the train, but you may have to stand. I just noticed that you can get seat reservations from Linz to Munich on that train, which means you might have to stand for the first 1 1/4 hours and have a seat for the last 3 hours.
Go to www.oebb.at and you can get seat reservations from Linz to Munich.

will the tickets be honored on another train leaving earlier or later

A ÖBB Standard Ticket is valid for 2 days on any train, a "Comfort Ticket" is train specific but you can exchange it free of charge, cf. https://www.oebb.at/en/tickets-kundenkarten/weg-zum-ticket/basis-standard-komfort

but you may have to stand.

I think you have a good chance to get a seat from St. Pölten (after about 30 minutes). The RailJets serve de facto as commuter trains until then, after that the situation relaxes. You could also return the ticket for free and take the Westbahn instead (5 trains per day). Eurail passes are honored.

thank you! Very helpful information. I just booked two tickets from Linz to Munich and we are feeling much more relaxed about the trip. Will also try to catch an earlier train that might have seats in Vienna. If not, we'll just enjoy the ride. regards,
-Mike

You can also try to grab seats in the restaurant car when you board early. Have some snacks and refreshments for the start of the trip. I see that this train originates in Budapest and will arrive at Vienna Hbf at 12:21 on Track 8. Be there waiting and see what if that is available.

I went on this train already. The problem is that it originates in Budapest, i.e.arriving in Vienna nearly full, lots of passengers without a seat reservation. So if you have one, you must insist on taking your seat.

these comments are all very helpful. thank you.
we are wondering if we have a better chance of getting a seat (or at least operationalizing the restaurant car strategy, above) on an earlier train, assuming of course that my wife's ticket for the 12:28 pm train would be valid on an earlier one.

All the trains from Vienna to Munich from 10:28 onward show "high demand" on the Bahn website. 8:28 shows "medium demand" and 6:28 shows "low demand". FYI

Sunday May 7th is ages away. Trains do not "sell out" weeks in advance. If they would they would be useless. in practice trains do not sell out at all.

If you see that you cannot reserve seats on a train that is more than a couple of hours in the future then the real reason is that the seat inventory has not been loaded, or that it is simply not possible at all to reserve a seat. On trains in Austria (and other countries with proper railways) it is not necessary to have a reservation to board a train. So you can always board the train. A reservation guarantees you a seat, but is not needed. Most people do not reserve seats when travelling. Trains are mass transit.

Now with a pass you can just take another train. With a normal ticket you can also take another train. Only with a discounted ticket are you limited to a particular train.

If you really want reservations just wait till you are in Austria. You should be able to get reservations for any train on the 7th at the station n Austria, up to the moment the train leaves.

again, all comments very helpful. our anxiety level is significantly lower than before starting this dialogue. we'll probably just wait and see, knowing we have some good options. thank you again.
-Mike