The Alpha version of the Ares uses the model of an SDF Destroyer. In the final game it uses the model of an SDF Carrier.
Strangely, the mission objective still identifies it as a destroyer. Furthermore, SDF troops who talk about the Vallis later in the game also refer to it as a destroyer.
During Operation Deep Execute, several SDF soldiers can be overheard discussing the destruction of the Vallis. It would appear that the SDF leadership has been disseminating false reports amongst the rank-and-file to cover up the fact that the carrier was destroyed by a small infiltration team, as SDF troopers seem to believe that the carrier successfully fought in operations on Luna, only to suffer a weapons malfunction, which prevented it from defending itself and thus it was subsequently destroyed. However another explanation also given to the enlisted men was that the Vallis survived the battle on Luna but later discovered an old Earth exploratory probe (apparently over 200 years old, though this account is entirely SDF propaganda) that was transmitting on an open channel. The Vallis is alleged to have taken the probe on board and discovered it was broadcasting music, speeches of liberty and historical accounts, as well as scientific discoveries. This was then, apparently without authorisation, broadcast to the whole of the ship's crew, causing a mutiny amongst the troops. The mutiny was stopped and agitators and officers responsible for failing to prevent it were to be handed over from the carrier to be executed. However, the ship never arrived at the assigned location, leading SDF troops to believe it defected.
Despite this, two soldiers seem to have heard rumours of the true explanation behind the Vallis' defeat and express shock that Nick Reyes and his SCAR team were able to pull the operation off, convinced that such a tactic wasn't viable. Despite doubting such an explanation is true, they quickly reassure themselves that if it was, then the SDF High Council will take steps to prevent such a thing from happening again and that the SCAR team responsible was probably led by an unusually competent soldier, unrepresentative of his comrades or SATO forces in general.