OK, I got there in the end. Quite enjoyable, I think. FOI 20, LOI 5, which I had never heard of, despite having lived in east London for 7 years, a long time ago. COD, either 12a or 19a. DOC (opposite of COD) 3d, because I think it's a remarkably weak clue, unless there's a clever second way of reading it which I have missed. I still haven't
quite forgiven Soup for slowing my start down with the misleading instruction, but I admit it was quite amusing once I realised, and after that it did help with a few clues.