This whole subject is a minefield of potentially getting it wrong!
I now especially get worried about wrongly addressing someone over the phone and tend not to use the Mr/Miss/Mrs or Madam/Sir forms of address, even though when addressing clients it has historically been the polite etiquette to do so! I now ask to speak to Jane Jones or whatever. The problem here is that some people object to being addressed by their names in this informal way and would prefer to be addressed by Mrs/Mr etc! I have to make a lot of calls to clients in my job and this is now a further level of anxiety especially if I have not yet met them and have no other indicator of the situation?
To obliterate your address on packaging