It's great that you were hopeful enough to get to this stage. Sometimes, they lose correspondence, or the envelope comes back to them even though you gave them the right address. That's what the officer told me at my interview. They sent my first interview letter to an old address and it was sent back to them so instead of having it in March I ended up having it in April. But it's fine now.
Good luck and for the BCG we have that too, but my kid was just born last year and in the US so we didn't have to go through all of that nonsense. They do push you around if you're not informed which is sad. Thanks for the tips, they will help someone else I'm pretty sure.
We moved in Dec 2009 (two months after DV entry). We had the old address in the entry because we didn't know if we are moving at that time. We used to get all credit card bills, other bills, spam and all sorts of stupid mail forwarded to our new address for a year. I guess with so much other stupid mail there wasn't room for the ONLY ONE IMPORTANT
...and the DV fee receipt was all wet and I am pretty sure I don't have a leak in my mailbox. Nothing else was wet and the receipt envelop was at the bottom. It was one of those priority mail flat rate envelops so it took a lot of dripping to get it that wet. Thank you US Mail!