There has been much uncertainties and contradictory news around the China Eastern Airline (SIA-CEA) deal, including an attempt by CA/CX for a competitive bidding.
IMO the CA/CX deal is impossible. It is just something CNAC/CA tried to force SIA to raise the price (CX, being CA's partner and very interested in the China market, can only oblige to join the show). Merging CA with CEA will be an anti-trust issue and I am sure the PRC government does not have appetite to deal with such complication at this particular moment.
What CNAC really wanted is for SIA to raise the price. This is natural and reasonable from a shareholder's perspective, when the current market price is more than double the proposed deal price (HK$3.8) for SIA.