When looking to book a Eurostar ticket, I discovered that it was cheaper (for this one journey - no promises in general!) to book it via the SNCB English website rather than via Eurostar themselves. So, having double checked the numbers (including credit card fees, also lower with SNCB), I opted to book my ticket on the SNCB website.
However, at no point in the booking process did I spot anywhere to enter my Eurostar Frequent Traveller details. Now I've booked, I can't see how to change it on the SNCB site. If I go to the Eurostar site and do Manage My Booking, it shows the details of the trip, but doesn't let me change anything, so I can't therefore enter my Eurostar Frequent Traveller details there.
The worst case is that after the trip, I can log into the Eurostar website, and do a missing points claim with the ticket details. However, that's a bit of a faff, and I need to remember to do it, no sooner than 1 day after the trip ends, and no later than 3 months. Given that, I'd rather enter the details now while I'm thinking of it!
So, is it possible to attach Eurostar Frequent Traveller details to a booking made via SNCB, or is my only option the missing points claim later (assuming I remember....)