This last weekend DB has indeed (unfortunate clash of circumstanes) partly completel set its won and usually quite good- IT system to other ways of handling (mostly for those having BahnCrads or other discount means or frequent customer, like me too).

Do not fear too much about ´full´ness and even in that case for this train: use other WAW trains to Poznan and change to PKP. Try again (bring plenty of time) in the Reisecentre closest by Berlin. Extra cost is about 6-7€

Someone else told me/I read one can now do it via DB-machine (it also gets fields for NUr Reserv after you have chosen train) but for me (I tried this out 2 days ago) it would not work.

Probably the Polish reservation system has crashed again. This happens from time to time. If the Polish system is down, then reservations are impossible to make.

Are the reservations mandatory on the train? I guess that even if they are. you should be able to travel with the train if reservations are impossible to make.

Yes they are mandatory when you travel International or within Poland as these Eurocity have are the second highest service in Poland.

Hi @lovi500

Did you manage to get a ticket ok?

I'm doing this journey (Berlin > Gdansk) at the end of July and it's the only part of my journey I'm having problems booking.

It would be a relief to know I can get the ticket the day before in Berlin. 

Thank you,

Hi @Helsbells73 , Yes I did manage to get the seat reservation at the DB Reisezentrum in Berlin; luckily I had enough time before my train left to get a seat ticket! I think I paid 4,5€ for the reservation :)