Your first, and most important lesson, Matty...
Dont ever trust any advice any department at the CAA gives you over the phone. Its always subject to misunderstandings (not necessarily your's).
Always get a query answered in writing.You then have a comeback when required (and that may be quite often)!
Now, you should book immediately for an Initial Class 1. No if's, no but's.
You will be sorry if you spend more money hour building and then they find an unknown problem. Even their website gives this advice.
Good luck.