I believe such a change would be ill-considered, just now when we are claiming to be the faithful heirs of Archbishop Lefebvre.
What is this nonsense? I thought we're interested in the truth and not some kind of political machinations around who can rightly lay claim to some meaningless title such as "faithful heirs of Archbishop Lefebvre"? Archbishop Lefebvre changed his mind over the course of the years, and could very well be a sedevacantist right now given the phenomenon of Bergoglio. He nearly went SV at Wojtyla's Assisi meeting, and Bergoglio makes Wojtyla look like St. Pius X by comparison.
Is +Lefebvre some kind of infallible rule of faith or something? Did he have a single consistent position on every issue during his entire life? During the early 1980s, his thinking differed very little from that of +Fellay and his neo-SSPX now. As Matthew pointed out, the situation had changed since then. And it's changed again since the Archbishop passed away. So what makes anyone sure whether or not he would have changed again in response to Jorge? Nothing.
We seek the truth and not some political nonsense about being THE faithful heirs of +Lefebvre. To outsiders, this is ludicrous. "We're the faithful heirs of +Lefebvre. No, you aren't, we are. You're unfaithful to +Lefebvre. I know you are, but what am I? I dare you. I double dare you. I double dog dare you." How puerile.
Part of this comes form the fact that R&R want to fill the vacuum of not having (what they claim to be) the Magisterium as their rule of faith, by coming up with a substitute rule of faith to fill the vacuum, and so they set +Lefebvre up in that role, something which I'm sure he would have eschewed.