Thanks for the responses. Once I thought about it, it made sense that I'd need to update the form. I was just stuck on my "but I wasn't even gone for an hour" logic and needed confirmation.
I have read horror stories about every consulate in SE Asia, and I had other reasons to be in Hong Kong. I had asked about the location in this group several days ago before we booked tickets, but only got responses that my 3 previous visas could but shouldn't be an issue if I had all my other documents.