Well I used the link as shown above and eventually got an email back which confirms the cancellation but no price, no breakdown of costs etc despite choosing the appropriate option in the list. So basically all I got was exactly the same as I was originally sent i.e confirmation of the cancellation and the ticket numbers but nothing else.
Any idea if it's worth giving customer relations a call or is there anyone else I should be contacting about this, the clock is ticking on my insurance claim so I want to get it sorted ASAP.