A Birthday Card has arrived for one of the Hoors...
Miss Diane must be celebrating a birthday, and just to make sure it gets to her and not to any other Miss Dianes in the building, the sender has specifically written "right hand buzzer" as part of the address. (They have a separate buzzer from everyone else, because they are lovely ladies and don't want any of the rest of us getting bothered. Either that or because they don't want any trade going anywhere else).
There is even a heart as the dot above the "I" of Diane!
how sweet :)