Yes, Saber's (Arthuria) situation as a Servant is unique. She is not a true heroic spirit, but rather an incomplete one (See: Fate/Zero novel, Vol. 2, Act 5, Part 1):
As Saber - that is, Arturia - is an incomplete Heroic Spirit, she would not possess the knowledge that surpasses time and space one gains when one has reached the Throne of Heroes.
According to the Type Moon Wiki:
Heroic Spirits are those who have been removed from the time axis and placed on the Throne of Heroes, while Saber can still be considered living. The hero known as King Arthur is not currently classified as a Heroic Spirit, so she cannot be called a complete Servant. She made a pact with the World as she was on the verge of death after the Battle of Camlann that will require her to become a Counter Guardian, a subcategory of a Heroic Spirit at the service of the World, after her death. These pacts are normally done by those requiring the power beyond ordinary humans to become heroes during their lifetimes, but her wish instead came at the time of her death because King Arthur did not require support to become a hero.
Having technically not died yet, Saber cannot take on Spirit Form like most other servants because she's technically still considered alive. This allows her to keep all memories of her search for the Grail, unlike Heroic Spirits don't keep their memories in order to prevent inconsistencies.
With that being said she most likely realizes the positions she is in and the recurring characters, but does not act upon it would complicate matters (singling her out as an irregularity, raise unnecessarily questions that may distract her master).