Never, I am going to believe your source because to me, it just makes sense. When one is around a large corporation for a long time; if you pay attention to business and what is going on in your corporation, yes I agree one will hear these things. Generally, the lower level people who keep themselves informed about what is going on may not have the dates correct, but they do get it.
I will use a merger for example, these people at the corporation will know ahead of time that a merger will happen and will even have it narrowed down to one or two other companies the merger will involve. Generally these people will not have the exact time line and maybe several months off, but they will know way ahead of the announcement. Same principle appies to this WaMu example, but the timeline is very close and no doubt IMHO.
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