It was 67 years ago that the only person ever to be fired by the Grand Ole Opry got the bad news. In the 1979 Waylon Jennings/Hank Williams Jr. tune ,The Conversation, Hank says,

Most folks don't know that they fired him from the Opry
And that caused his greatest pain
Yes, Hank Jr.'s Daddy was the only person ever actually fired from the legendary country institution. Hank Sr. had become very undependable as an Opry performer as he sank deeper into booze and pills but it was his no-shows at Opry sponsored concerts on the road that finally made the decision inevitable. Hank died about four months after he was let go.
There have been several artists that have been suspended for various reasons and eventually allowed to return.
Johnny Cash
In 1965 Johnny took the stage at the Ryman auditorium drunk and got upset at a member of the audience and ended his performance by taking the microphone stand and smashing out the stage lights. He was suspended but after just one year he was asked to host the Opry TV specials so they kissed and made up.
Skeeter Davis
It was 1973 when Skeeter was scheduled to perform and before her show she went shopping at a Nashville mall. A group of followers of Bill Lowery's Christ is the Answer Crusade were in the mall approaching shoppers who complained to police. The Nashville police arrested about a dozen of the demonstrators. Skeeter then drove straight to the Opry to do her show and began her time on stage ripping the Nashville police department and then sang "Amazing Grace". She was suspended for a year.
Jerry Lee Lewis
It was 1973 when Jerry Lee was invited to perform at the Opry and told there were two rules: No cussing and he could only do his country songs and could NOT do any of his old rock hits. And, oh yes, he could only sing two songs. Without going into detail just let me report that Jerry lee proceeded to violate all the Opry rules on live national radio and was never asked back. Singing for 40 minutes was the least of the Killer's violations.
Deford Bailey
we're going way back for this one. Deford was the first African American member of the Opry and came on board in 1927 when the show was known as the WSM Barn Dance. He was an expert on several instruments but it was his harmonica tune "Pan American Blues" that gave him a big hit and made him an Opry favorite from 1927 to 1941. In '41 there was a  fight between the music licensing groups ASCAP and BMI which resulted in Deford not being allowed to play his popular tunes on the Opry so they let him go. He did come back for an old timers show in 1974.
Right now there are 68 Grand Ole Opry members. Each is required to do 12 shows a year at the Opry  to maintain their good standing. Sometimes artists are unable to meet that commitment and are temporarily suspended. If they continue missing their required number of shows they can be dropped from Opry rolls. It should probably be mentioned that artists don't get paid much for making an appearance at the Opry. It's Union scale which they say is less than $200. The big stars get the same as the newcomers.
The youngest current Opry member is Kelsea Ballerini at age 26 and Jan Howard is the oldest at age 87.