I came across an appeal decision on the US Appeals Committee page answering an interpretation requested by the Noroton Yacht Club. Published in February: Question 100
In it the US-Appeals Committee states that it is a proper action for a race committee to abandon a race for one of the reasons listed in rule 32.1(a)-(e) after all boats have finished or retired. There is no need to do this on the water, and if ashore, posting a notice is sufficient. The RC can take this decision provided it first considers “the consequences for all boats in the race or series.” And there's no time limit to take this decision.
So far I don't disagree with this interpretation of the rules. But personally I would need a very powerful reason to ever to this. And doing it after protest time has ended is showing disrespect to the sailors.
The first reasons to abandon a race RRS 32.1(a) trough (d) all are reason which occur during the race. Only in 32.1 (e) there might be a reason which only becomes obvious after the race, like in this appeal question, the appearance of fog and the influence it had on the race. Nevertheless all sailors finished the shortened course. If we go with the "fairness" of the race as an argument to abandon, I would be very reluctant to do so other than based on an argument of several - if not the majority - of the sailors. In my experience there are always one or two sailors who think that a race wasn't fair - sometimes solely based on a their finishing place.
And perhaps a time limit on a decision like this would be needed too. Imagine abandoning the first race of a series on the final day five minutes before price giving. That would constitute an improper action in my opinion, although the rulebook doesn't say it is.
What is your opinion?