It says in Nida (7) that during Rabbi Eliezer's life the Halacha was not followed according to his opinion (his opinion in the Mishna is that four woman receive the status of dayan shaytan). However, after his death the Halacha was followed according to his opinion.
כל ימיו של רבי אליעזר היו עושין כרבי יהושע לאחר פטירתו של רבי אליעזר החזיר רבי יהושע את הדבר ליושנו כרבי אליעזר בחייו מ"ט לא משום דרבי אליעזר שמותי הוא וסבר אי עבדינן כוותיה בחדא עבדינן כוותיה באחרנייתא ומשום כבודו דר"א לא מצינן מחינן בהו לאחר פטירתו של ר"א דמצינו מחינן בהו החזיר את הדבר ליושנו
All of Rabbi Eliezer's days, they would act according to Rabbi Yehoshua's opinion. After Rabbi Eliezer's death, Rabbi Yehoshua returned the law to its former status. Why could't the law follow Rabbi Eliezer during his life? Because Rabbi Eliezer was banned, and it had been thought, if we follow him in this one law, we might end of following him in other laws. Since we have great honor for Rabbi Eliezer we would't be able to protest his other laws. However, after Rabbi Eliezer's death, when we are able to protest his other laws, Rabbi Yehoshua returned the law to its former status.
To what former status was the law returned to? The text itself reads that the law did not follow Rabbi Eliezer during his life, if so there was no former status to be returned to.
This is the question of Rashah if I'm not mistaken.