Unable to reserve seats Angouleme to Strasbourg

Strange, I've now gone back to the journey planner on my pass, and it's showing that I CAN reserve seats now. Is it perhaps question of a delay in the app getting the necessary information?

However, the B-Europe website, which I went to to make the reservation still shows "booking momentarily impossible"?

Note: it's cheaper to book on www.raileurope.com (desktop website only) and you can indicate your seating preferences.

Maybe they've opened a bit early. Although on the SNCF website you can't book yet, so I doubt it.

In addition, the app doesn't know which reservations can be booked (and can't book anything), so what makes you think you can already book? The price it shows is just retrieved from a database at Eurail.

I had no luck booking my Eurostar on the Raileurope website, I couldn't find a way of getting the pass holder price but the B-Europe one worked fine. I was trying to use the Raileurope one on my phone, is that the problem, since you specifically mention the desktop site?

That was most certainly the problem. The Rail Europe app can't book pass holder reservations and neither can the mobile website. You either have to use your mobile browser's option to show the desktop website or use an actual pc.

Just to be clear, the journey planner in the Interrail app initially said that seat reservation was mandatory but n/a. I went back to it later and a price had appeared. 

I'm a bit surprised that reservations open so late, it's only 10-11 weeks away, I would have expected them to open a minimum of 3 months before travel but clearly that's not the case.

Thanks for your help, I'll try Raileurope on the desktop site.

That however does not say anything about whether reservations can be booked. N/A just means the app can't retrieve the prices. I tend to ignore them anyway because there are many errors.

SNCF open reservations in blocks, as you can see on their info page. They've been doing that for quite some time.

Thank you rvdborgt, I have now booked all my seat reservations for the French leg of my journey on the Raileurope desktop website today. 

It's a minefield to work out the various things that aren't clear - I didn't know that SNCF released bookings relatively late, nor did I know that seat reservations could only be made on the Raileurope desktop site.

Yeah they like to release tickets in batches. For example trains until 22nd May were already on sale for a month and a half…

SNCF removed that option from their website as apparently too many people “misused” the option and bought a reservation without having a pass.

Enjoy the trip!