Don Johnson

Act 6:2

And the twelve summoned the full number of the disciples and said, “It is not right that we should give up preaching the word of God to serve tables.

The question I would pose to you is how would the original reader understand this, specifically, what is meant by the twelve?

My claim is they would read it as including Matthias and the 11, since that is what was done in Acts 1.  They would not think it is just 11 and that the 11 made a mistake in choosing Matthias.  There is no claim in the Bible that they made a mistake in Acts 1 to Acts 6 and Paul is not yet a follower of Jesus.