Romans 4
Does Paul speak of Abraham after his circumcision?
Not with regard to Abraham's justification without works.
Rom 4:1-5 What shall we say then that Abraham our father, as pertaining to the flesh, hath found? (2) For if Abraham were justified by works, he hath whereof to glory; but not before God. (3) For what saith the scripture? Abraham believed God, and it was counted unto him for righteousness. (4) Now to him that worketh is the reward not reckoned of grace, but of debt. (5) But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness.
The "what saith the scripture?" refers to this:
Gen 15:6 And he believed in the LORD; and he counted it to him for righteousness.
Circumcision does not come until Genesis 17, so YES Paul is referring to Abraham in his UNCIRCUMCISION.
Could Paul be any clearer?
Rom 4:10 How was it then reckoned? when he was in circumcision, or in uncircumcision? Not in circumcision, but in uncircumcision.
James on the other hand, refers to Abraham offering his son.
Jas 2:21 Was not Abraham our father justified by works, when he had offered Isaac his son upon the altar?
This is recorded in Genesis 22, AFTER Abraham's circumcision. So YES, James refers to Abraham in his CIRCUMCISION.