A friend of mine is moving March 30th. He has 2 roommates, and all are moving out, to different locations. So his census asked “How many people will be living in this household as of April 1st?” He answered “0”, answered the second question (about whether it was an apartment or a house), and mailed it in. There was nothing else he could fill in.
Without knowing the proper procedure, I would have filled out the form as to what his living situation was going to be on 1 April (and if necessary included a little note correcting the address.)
Wait a minute… April First? Are you pulling a fast one on us?
I had a tough time with this one myself. I had no intentions of filling out my own census form until April 1, which is the “effective date” of all the questions. But I kept getting letters from the Census folks, saying, “hey, you gonna send that thing in or what?”, so I filled it out and sent it in.
I think quadell’s friend filled out his form correctly.