Yes, Bishop Anthony Pilla of Cleveland has asked to be able to resign, two years before the mandatory retirement age. He hasn’t said why, but it’s no secret that he’s had health problems in recent years.
But asking to resign is not the same as being replaced. The process of finding a replacement may take some time, especially since there are five vacant sees currently and eight more bishops who are serving past the age of 75. Another eight bishops will turn 75 this year. Plus Archbishop Pietro Sambi, the apostolic nuncio, is newly appointed and it will be a while before he can start submitting the terna to the Congregation for Bishops.
If Pilla had a need to leave immediately, he would have stepped down and an apostolic administrator would have been named. That he’s staying in place while a replacement is found says this is not an extraordinary situation.