When calling one financial institution about the bereavement, the operator asked to speak to them I politely explained again they had passed and it was ok after that.
Generally though most places have been ok, one tip for anyone dealing with POA or Bereavement is to call M-F during office hours. It's because most of the teams that deal with that don't work weekends or evenings.
I've found that too. While they can't short cut a process , they have all been very kind and helpful in as much as they can. Most financial institutions seem to have a bereavement team