0BB RailJet and 1st class FIP coupons

Can anyone tell me exactly what classes of accommodation a first class FIP coupon is valid in on an OBB RailJet service (I understand there are 3 classes of accommodation). The ATOC guide is not very clear on this.

I'd expect first class (the open coaches), as the business class compartments require an additional payment of EUR 15 on top of the first class fare.

Neil

ATOC guide states ...'Premium class in railjet services may not be used by holders of any FIP travel facilities.'
So if you have 2nd class FIP you use 2nd class, if you have 1st class FIP you use 1st class.

It also depends on where you are travelling. For example if you are travelling between Munich and Salzburg on an ÖBB railjet, DB's conditions of carriage will apply where a Business supplement is not required. Ask train staff politely when in doubt.

When I came back from Budapest to Munich, I paid the €15 supplement to sit in business from the MÁV conductor without a problem.

In my experience, FIP 1st class coupons are fine in the 'Business Class' = normal 1st (2+1 seating) but not in 'Premium class' (1+1 seating in compartments). The ATOC guide is ambiguously drafted, but I think that what they mean is 1st = Business, 2nd = Economy and no FIP at all in Premium. However, in Austria you will find the odd conductor that insists a charging a supplement for the use of the FIP coupon (of about EUR3 per journey). Having checked this over and over again with OEBB staff at stations, this is not the case. But a number of conductors have I met have been quite insistent that this is the rule: I expect this is something from the past that has now been dropped but not all staff have clocked it.
The other thing about Railjet services in Premium class is that they have friendly at-seat service of food and drink: one has to pay but it's very good value (a bit like GNER was once upon a time). This is really the only railway in Europe left doing this in my experience!

I think your use of different class names is a bit confusing, there hasn't been anything called "premium class" for a couple of years.
They are now just called 2nd class, 1st class, and Business class.

http://www.seat61.com/railjet.htm
http://www.oebb.at/de/Services/Zuege_und_Ausstattung/Wagenausstattung/index.jsp

Having now been I can confirm there are three classes "Economy", "First" and "Business". First Class FIP is valid in "First". ATOC need to drop the term "Premium" in their guidance and make it clear that First class FIP is valid in "First" but not in "Business". Thanks for all the responses.