When I sent my FiT paperwork to Scottish Power (who were satisfactory considering the mad rush) I sent everything possible, so as to avoid any problems or hiccups. My biggest concern was that if anything was not how they wanted it, that it'd take them a month to return my "unsatisfactory" application and that I'd have risked falling on the wrong side of the FiT timeline. Rules mention FiT is payable from the date of "receipt of a satisfactory application" - so, in theory, some jobsworth might claim that my application wasn't adequate and I'd miss the cutoff because when I have finally sent-in a "satisfactory" application that the date was into a different FiT payment band.
As it happens: the date of eligibility for my FiT turned out to be dated four days after the commisioning date of my system, so clearly things aren't always backdated. I wonder how that would stand if I was installed today but the FiT paperwork ends with with next Tuesday's date on it. My guess is that it only becomes eligible for a 21p FiT.
When we were talking the difference between whether I might get a 43p FiT or a 21p FiT for the next 25 years, it seemed a small precuation to take.
It was quite a chunky envelope, sent via Royal Mail Special Delivery in order to get there as soon as possible.
In my envelope was:
FiT application.
Copy of MCS Cert
Copy of schematics
Copy of electrical installation certificate
Copy of G83/1 form
Bank statement (as proof of name, address and the account to which FiT payments were to be made)
Copy of invoice
Maybe something else - I'll add it later if I think of it.