I don't know what they've done. I looked through Whitechapel and Bethnal Green Districts for 1901 and although there were many address in Brick Lane, and I've now found them down to about 42, I couldn't find number 4. It's not a satisfactory way to search for addresses though. That is something the old FindMyPast site was really good for, but I guess like everything else that was good on the site, it's gone for good.