The Gemara on Ketubot 45b analyses the statement of Rabbi Shimon "Mishenitmanu Peturin."
Why does the gemara not suggest the following explanation-
... Rebbi Elazar said that a person is not elevated to greatness unless all his sins are forgiven (Sanhedrin 14a)?
The fact that one is forgiven does not exempt him from the Chiyuv Chatas which he must have for Kaparah. Even Yom Kipur, which also is Mechaper, does not exempt one from a Chatas.