The "official" story goes back to February, right? Danny tells Wyc he's thinking of retiring and Wyc goes to Brad and asks him if he's interested in Danny's job. I'm sure there's a combination of truth and spin to that general timeline of events.
Interesting that Wyc said Brad could probably still be the coach if he wanted. He also said the front office job and head coach are two different jobs with the Celtics, which would mean Brad had his choice of one but not both.
Danny also recently hinted that his engagement (delegating to others in the front office) might have to change. At the time it seemed he might be stepping back in to do less delegating. Was that the case at the time? Or was he referencing stepping away? Perhaps nothing was official until the end of the season. But certainly I think they all discussed the possible plans for a while before that.