Yom Kippur is a time of reflection, repentance, forgiveness and drawing close to HaShem. Many themes revolve around redemption and being written in the Book of Life. It is critical to understand that Judaism and Conservative Messianic Judaism do not teach redemption (Salvation) by works as many in the Church might misunderstand. The Kol Nidre Service contains a beautiful prayer which says "we have no works that commend us to you". This is important, because in many ways it transforms the meaning about Yom Kippur and clarifies many misconceptions.
Is Yom Kippur about Salvation? This is a little more complicated than it might seem. In the context of - does Yom Kippur allow the person to be written in the Book of Life for another year, then it is a type of physical salvation from death. From an Eternal Redemption prospective though we must look beyond the actual literal meaning to the Spiritual reality of Yom Kippur.
What is Redemption or Salvation? In Jewish terms what many refer to as Salvation is seen as belonging to HaShem. Since Jews and in particular religious Jews clearly identify with belonging to HaShem then the Christian concept of "being saved" has little to no meaning. So what is a more universal concept of Redemption (Salvation) that encompasses both views, belonging to HaShem and redemption in Messiah. I think the answer is trusting / relying on HaShem.
So using the more universal trusting / relying on HaShem the question becomes, is Yom Kippur about trusting in HaShem? To both traditional and Messianic Jews the answer I believe becomes the same. Yom Kippur is a result of trusting in HaShem.
If this is correct, then we transform many peoples understanding of Yom Kippur from a supposed "legalistic" act to somehow "earn" redemption, and instead see Yom Kippur for it's true meaning, an beautiful expression on trust / relying on HaShem. Yom Kippur in that light is transformed and if we let it's meaning sink into our being, transforms us in to servants of the Most High.
Baruch HaShem - Rabbi Gavri'el