The time on the reservation is correct as the reservations always are made with the railway company even when you make the reservation through Interral/Eurail.

Then, there might be changes due to circumstances not known in advance to the railway company so you should always check departure times with the timetable of the railway company you will be travelling with. Personally I always download the apps for the nation railway companies for the countries I travel in.

@AnnaB  Thank you. That is very helpful. Is there a list of European train apps anywhere. I do not know the names of the rail companies . Thanks again.

Nothing in life is 100%. In general yes, 98-99% will be correct. IF you had booked DIREct by railway-and sometimes give permission (extreme privacy laws) they can contact you, they may send mail that train is cancelled/rerouted/delayed etc IF-of course-they know that enough in advance.

I very often book via bahn and they now even send me mails that the train I am waiting for is 10/15 ins late-but I can see that too on the screens if I wait

BUT there are always mishaps-and this summer it seems a fair big lot-derailments, blocking of the line, waterfloods, etc.-so you also always have to look in the station to the screens etc-there have been cases where people missed trains as they did not look up form their fones……..

Another plague for some is the very often-and not always announced in time-change of tracks/platform at last minute. Like the DSB/danes could manage yesterday eve-even 2 times.

@mcadv Many thanks

Almost all reservations include the train number and will always give the scheduled date and time at time of issue. Your reservation will always be valid for that train number if time is changed.

As other posts have said changes can occur, but these are infrequent and normally easily fixed by simple checks on planners and apps.

If you find yourself in a station and your train time is changed or even cancelled, check with local staff for alternatives and see if they can amend your reservation. Remember your pass is totally flexible and you can use it on any alternative train (subject to reservation requirements), Train inspectors will normally be helpful if you have been affected by a change.

I don’t believe there is a single list like that, certainly not an official one.

I would recommend both the German operator “DB Navigator” and Austrian “OBB Scotty” apps, these cover most of Europe and they will also list the operator of each train so you can check the website or download local app should you wish.

@Al_G  Thanks that is very helpful.

If you say where you are trvelling, we could give you some advice which apps you could use.

Via bahn.com you should see most of the trains in Europe with live data for Germany. There you can see often also who is the train company that operates the trqin.

@Angelo  That is very generous of you.

France Luxembourg Belgium Italy Germany Netherlands Austria Switzerland.

@AnnaB I loaded an app called OBB which has terrible reviews. Is OBB Scotty a different company?

I have found and loaded the DB app.

I am confused when should I use BAHN.com instead of the DB app, is it for trains outside Germany?

Do I have to use each countries app to make reservations? Is there no ONE site which can reliably make reservations around Europe? I have seen elsewhere that it is better to make reservations NOT on Interrail if I can.

Thank you all for such great help. I am gradually summarising everything I learn and adding it to my first post here - titled NEWBIE.

• France: SNCF Connect, you can’t book no reservations for Interrail Pass users on this site/app. The website/app is terrible, but you have to live with it. 
• Luxemburg: No idea, but the train company is CFL. https://www.cfl.lu/en-gb. Keep in mind, that all public transport in Luxemburg is for free. 
• Belgium: https://www.belgiantrain.be/en SNCB/NMBS
• Italy: Trenitalia.com, reservations for Interrail users via Austrian Railways ÖBB via ÖBB App or tickets.oebb.at
• Germany: bahn.com DB Navigator App
• Austria: ÖBB App is to buy tickets, ÖBB Scotty App is to search for trips, a travel planner. It is the same company.
• Switzerland: SBB.ch, you could also write the tracks on a paper, because railways in Switzerland run like a Swiss watch, most of the time. Map of all train lines where Interrail is accepted: https://www.sbb.ch/content/dam/infrastruktur/trafimage/karten/karte-geltungsbereich-InterRail-EuRail.pdf
• Netherlands: NS.nl 

Most trains you will find on bahn.com or DB Navigator APP or the other apps of the other train companies. But for live information, if the train has a delay, a cancelation or another track than planned, you need to use the app of each train company. 

P.S. Public transport in the is not included in the Interrail Pass, but like S-Bahn in DE, AT or CH is like a underground/metro system but run by the train companies and is included like in Berlin, Munich or Vienna. U-Bahn is the underground/metro system, and Interrail is not accepted. 

Reservations are usually correct about the Times. But in rare cases like booked months in advance or a accident on the route causes sometimes that the time on the reservations are not correct anymore. 

Because of that I Check usually 24hrs before on the railcompanies Website if everything goes like planned :)