2 Corinthians 3:6 - the letter kills

2 Corinthians 3:6
He has made us competent as ministers of a new covenant--not of the letter but of the Spirit; for the letter kills, but the Spirit gives life.

As Paul said, the new covenant is not of the letter but of the Spirit.
With this in mind, how do we interpret 1 Corinthians 5:7-8?
Get rid of the old yeast, so that you may be a new unleavened batch—as you really are. For Christ, our Passover lamb, has been sacrificed. Therefore let us keep the Festival, not with the old bread leavened with malice and wickedness, but with the unleavened bread of sincerity and truth.

Was he referring to both physical (the letter) and spiritual (the spirit) yeast in the context?
If so must we get rid of both physical and spiritual yeast in order to keep the Festival?
For how long do we keep the Festival?
Is wickedness allowed after the Festival?

Was he referring to both physical (the letter) and spiritual (the spirit) yeast in the context?
Think so. Maybe just the spiritual, but keeping the spiritual does not mean we have to abandon the physical. Romans 7:12 comes to mind. Letter is not equal to the spiritual law which is supposed to be good, right?

If so must we get rid of both physical and spiritual yeast in order to keep the Festival?
Yes, you're right.

For how long do we keep the Festival?
7 days.

Is wickedness allowed after the Festival?
No. We are supposed to replace it with the new leaven.

Is there any consequence not doing the physical?

What is new leaven?

Is there any consequence not doing the physical?
Maybe there are benefits to doing it. If the law is in your heart (not saying I do), do you need a consequence? Are the spiritual and physical necessary two different things? Why does someone have to be baptized physically if they can just be baptized spiritually?

What is new leaven?
My guess is the works of the spirit.

Does not physically remove leaven from our home affect salvation?

Must one be baptized to be saved?