Advice on Eurostar seat assignments

[luvgoing2disney]

We will be visiting the UK in late July and are going to DLP/Paris for 8 days as well. Our Eurostar train tickets were bought through our travel agent and we have the reservation number. I’ve read that you can select your seats but the ticket information we have so far is saying they will be assigned at check-in.
This is our first time on Eurostar so I was wondering if the seats CAN be selected by us or if we can see where we have been assigned. I tried to look through the Eurostar site last night but was not successful. Don’t know if buying the tickets through the agent might have caused that.

 

[CAL2]

Hi, we booked directly through Eurostar online and it allows you to select seats and gives you your seat numbers. You may need to go back to your travel agent and ask them.

 

[Jon84]

In my experience, if you book with a TA they assign seats for you, when you checkin they let you choose.