It cannot be done at least I think. Legal requirement for distance learning is like for pure classroom learning, I think 650 hours of theory. Difference is that with distance learning you have mandatory of 100+ hours in classroom and that represents brush up (or revision) course. School need to file proof that you were present on all ground school classroom sessions to local CAA. Once you have this requirement completed than you can get CCC (certificate of completion/diploma) which you submit to CAA to start exam procedure.