After filing the flight plan, I am unable to see ALL the information I had used to file, including POB, Dinghy info, etc. 

The email I receive contains the route and addresses.
And the website only gives me the option to delay or cancel.

Where has the rest of it gone?
I just want to check I had filed with the correct SAR info.

It's a tricky one. Item 19 isn't accepted by a large number of flightplan recipients, so the flightplan we send is actually broken down into two versions, the "short" version (which is ICAO compliant) and the "long" version which includes item 19. Which version the recipients get depends upon what they can cope with. What we put in to the confirmation email is the "short" version I'm afraid. If you contact support we can always fish out the long version for you, if you like.