In much the same way that marriage sacraments are annulled. Marriages formally recognized by the Church, officially recorded and declared, are later judged and declared to have never been valid from day one and not worth the piece of paper the marriage certificate was printed on. Now until the decree on nullity is declared the marriage is recognized as valid by the Church, even though in reality, in regard to the spiritual effects, and in the eyes of God, it never had any validity.
In this way, Bishop Fellay is asking the pope to recognize and declare the reality that the "excommunications" were never valid.
In other words, the Pope goofed?
This is what SSPX means by "lifting" the excommunications? An admission from the Vatican that they were never valid?
I understand "lifting an excommunication" to be similar to absolution in confession. The penitent confesses his sin, expresses sorrow and is absolved.
You guys want it the other way around?