Festivals, New Moons, & Sabbaths as Prophecy?

So let no one judge you in food or in drink, or regarding a festival or a new moon or sabbaths, which are a shadow of things to come, but the substance is of Christ.
Colossians 2:16-17 (NKJV)

Nothing overly exciting, but to take something out of topic/reference, there was something that i noticed here. Paul is talking to the church in Colosse about not getting stuck in legalism when he makes this statement; "regarding a festival or a new moon or sabbaths, which are a shadow of things to come". It's an interesting statement that Paul makes here. Basically, from what i can tell, this is saying that the festivals, new moons, sabbaths (important Hebrew days) are more than just reminders of things that have occurred in the past or should be done because God required it in the law. But this states that they are also prophesies concerning the future.

For example, Passover represents the day that the angel of death "passed over" the houses of the Hebrew people and brought about the rescue of the people from Pharoh's hand. Meanwhile it was also a prophecy and representation of Christ, His coming, and His purpose. The second example is The Feast of Pentecost (feast of weeks or first fruits). It was initially a reminder that God is the provider of the harvest. Thus the first fruits belong to Him. In Acts 2:1 the Pentecost brings new meaning in that it sees the "First Fruits" of the resurrection of Christ and the outpouring of the Holy Spirit.

What's interesting is that it appears that Paul is saying that the Hebrew festivals, new moons, and Sabbaths are prophesies for the future (shadow of things to come). Thus there is more there than meets the eye (not surprising considering) even beyond the then current fulfillments (see the previous examples). So what new festival/new moon/Sabbath fulfillments are still in store for God's people?