It does not matter how we define apostle. What matters is what Paul meant by apostle. And for Paul, that is someone who has been commissioned by Jesus. Paul saw himself as the last person that Jesus commissioned, and so as the last apostle. He specifically mentioned Junia and Andronicus as being apostles before him, as it is typical for Paul to mention apostles that precede him (e.g. 1 Cor. 15:3-8).
I don’t know, Skovand, you’re just going to ignore all the literature I cite? This work is important. It represents the highest level of assessed arguments on the issues.