I don't know if member's are aware, that if you book Amsterdam to London. Eurail have no direct trains, but you have to book 2 separate trains, one from Amsterdam to Brussels either IC or Thalys, change in Brussels and go through security, before boarding Eurostar.
I got caught out by the website and finished up with a Brussels to London ticket. I have to now book at extra cost Amsterdam to Brussels with all the hassle of security in Brussels, and making sure my train arrives early enough. But I can't do this until 90 days before.
I have tried to cancel or reschedule my trip through both Eurail and Eurostar to no avail, they just don't want to know.
I reckon they take your money then abandon you.
Be careful with booking on the Eurail website.