Equating the new UA/CO with the Soviet is the perfect analogy. Come to think of it... the Soviet was much better at keeping everyone informed. Often announcing 5-year and 10-year plans that always came out exactly as stated.

One may interpret the silence as "holding back back news" or "CO/UA has not yet made a final decision about all the details".

I still give them the benefit of the doubt, and think they will keep E+ on existing planes... might not have made up their mind about CO metal.
The important question IMO is whether newly deliveries will have E+ or not.